1. Reboot your computer and try the CD/DVD player again. Sometimes the problem can be resolved by doing this.
2. Purchase a CD cleaner for your CD/DVD drive, such as Fellowes CD/DVD Drive Lens Cleaner. It can remove oxide residue, dust and debris from the laser lens and may correct the problems causing an I/O error.

3. Try the CD in another computer if you have access to one just to see if it's the CD rather than the computer that is causing the problem. If you don't have access to another computer, try a different CD and see if you get the same error.
4. Alter the transfer mode on your CD/DVD drive. You can do this by going to the 'Start' menu, and then right-clicking on 'My Computer' and selecting 'Manage.' In the resulting window select 'Device Manager.' You should then notice in the right pane 'IDE ATA/ATAPI' controllers, you want to expand this by clicking on it, then right-click your CD/DVD drive and select 'Properties.' Next click on 'Advanced Settings.' At this point you should notice a transfer node box that signifies your CD/DVD drive; usually this is 'Device 1.' Finally, open the drop down menu and select 'PIO,' then click 'Ok' and exit.
5. Check to make sure all devices that are hooked up to your computer are turned on. For example, if you have an HP printer attached to your computer and it is turned off, this can cause an I/O error to pop up. As soon as you turn it back on, the I/O error should disappear the next time you reboot.
6. Download and run a registry cleaner on your computer. Often if Steps 1 through 5 don't correct the problem, cleaning your registry can.

1. Perform a file search for the 'msdatgrd.ocx' file on your computer's hard drive. Look in the 'C:\Winnt\system32' or 'C:\Windows\system32' folders since most system files are stored there.
2. Copy the file from another computer running the same operating system and service pack installation if it is not found. Paste it into the system directory of the computer that is producing the 'msdatgrd.ocx' errors.

3. Click on 'Start' and then select 'Run.' Enter the command 'regsvr32 c:\Windows\system32\msdatgrd.ocx' or 'regsvr32 c:\Winnt\system32\msdatgrd.ocx,' depending on the name and path of your system folder. Press 'Enter.'
4. Reboot your computer to complete the registration of the 'msdatgrd.ocx' file.

Is your Defrag missing, or just broken?
1. Open 'My Computer,' right-click on a hard drive and go to 'Properties.' Navigate to the 'Tools' tab.
2. Your Defrag is missing and needs reinstalling if: 1) the 'Defragment Now...' button is missing or grayed-out, or 2) when you click on it you get an error message reading, 'The Disk Defragmenter is not installed on your computer'. To install it, double-click the 'Add or Remove Programs' icon in Control Panel, click the 'Install/Uninstall' tab, and then follow the instructions on your screen. Skip to 'Reinstalling Defrag.'

3. Your Defrag is broken and needs repairing if: 1)you are able to open the Defrag program, but nothing happens when you click 'Analyze' or 'Defragment,' or 2)You receive the error message, 'Windows cannot connect to the Disk Defragmenter engine.' Skip to 'Repairing Defrag.'
Reinstalling Defrag
4. In your main hard drive, find the c:\Windows\Inf directory. If your system directory is not on your c: drive or not named Windows, find it by clicking on 'Start,' then 'Run' and typing %Windir%\Inf in the box.
5. Find the file named dfrg.inf.
6. Right click the file and select 'Install.'
Repairing Defrag
7. Click 'Start,' then 'Run,' and run this command: regsvr32 dfrgsnap.dll
8. Click 'Start,' then 'Run,' and run this command: regsvr32 dfrgui.dll
9. Run Defrag.

1. Click the 'Start' button, then enter 'Dcomcnfg' into the search box and press 'Enter.' Wait while Windows configures and launches the Microsoft Management Console (MMC) Component Services Snap-in application.
2. Double-click the 'Component Services' link in the left side of the MMC window. Double-click the links underneath to navigate to 'Computers' > 'My Computer' > 'DCOM Config' > 'Microsoft Windows Remote Shell Host.'

3. Right-click on 'Microsoft Windows Remote Shell Host,' then click 'Properties' when the pop-up menu appears. Wait for the 'Properties' window to display, then click the 'Security' tab in the 'Launch and Activation Permissions' area.
4. Click 'Customize' and then the 'Edit' button. In the 'Edit' window, assign the following permissions:'Everyone -- Local Launch and Local Activation''Network Service, System, Administrators Group, Interactive--Local Launch, Remote Launch, Local Activation and Remote Activation' (enable all of the checkboxes)
5. Close the MMC snap-in utility. Reboot the computer for the changes to take effect.

1. Restart your computer in safe mode. If the computer is non-responsive, hold the power button down for 10 seconds or until the computer shuts off. Press the power button again and as the computer starts up, hold down the F8 key until the Boot Menu appears. Using the arrow keys, click 'Safe Mode' and press 'Enter.' Booting in safe mode will take much longer than a regular boot up. Log in as administrator by entering the administrator password in the 'Password' field. If there was no administrator password set, leave it blank. You can also log in as any user with administrative access.
2. Use your anti-virus software to scan your computer for viruses or spyware. Choose to scan all files on all hard drives. This may take a long time depending on the size of your hard drive and speed of your computer. After the virus scan is complete, delete all detected viruses. Refer to the anti-virus user documentation for more information on running a complete scan.

3. Run System Restore by clicking 'start,' then 'Help and Support.' Under the 'pick a task' tab, click 'undo changes to your computer with System Restore.' Click 'restore my computer to an earlier time' and then click 'next'. On the calendar, click a bold date from the calendar prior to the date you noticed the error. Click 'next' and follow the onscreen instructions.
4. Install the latest service pack for Internet Explorer 6. Microsoft Support article 328548 notes that IE group policies may cause an access violation in Winlogon leading to the C00021A error. Alternately, installing the latest service pack for Windows XP will install Windows critical updates as well as IE updates.
5. Restore the default Windows Graphical Identification and Authentication (GINA) file. Microsoft Support reports that many STOP 0xC000021A errors occur because the GINA file has been replaced by a third-party program (see reference 1). To verify your GINA version, click 'START', then 'Run'. Type 'regedit.exe' (omit the quotes) and click 'OK'. Scroll down to the following registry key 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon' and on the right hand pane look for the value 'GinaDLL'. Double-click this value and in the window that opens ensure that 'value data' is set to MSGINA.DLL.

1. First try to run the disk repair utility by using an alternate boot-up process. Turn your computer on and tap 'F8' while it's booting (or whichever key is listed on your screen during start up). This will take you to a boot menu with boot options presented. Choose 'Safe Mode' and continue booting. This mode is a stripped-down version of Windows without most drivers loaded.
2. Go to 'My Computer' from the 'Start' menu and highlight the drive on which you're experiencing the NTFS errors. Right-click on the affected drive and choose the 'Properties' option. This will open the drive properties window. Select the 'Tools' tab and select the option to 'check the drive for errors.' The system will then run through the drive check utility, repairing the NTFS error present.

3. If that isn't successful, access the repair console by placing your Windows System Installation disk into the drive. Turn your computer off, and then turn it on again to load the disk. Choose 'boot from disk in CD-ROM drive' during your computer's boot-up sequence (tap F8 as you did before to enter setup and change the boot option). Choose to enter the repair console when offered the choice on screen. The repair console will appear as a text prompt, for example 'A:\>.' Enter 'chkdsk a:' with the actual drive letter of your troubled drive replacing the 'a:'--chkdsk will run on your system and repair the NTFS error on the affected drive.
4. Move the drive to a second PC if the affected disk is your boot hard drive and you cannot access safe mode and your system installation disc is unavailable. Connect the hard drive to the second PC and use the safe mode on the unaffected PC's operating system to repair the drive.

1. Press 'Esc' if you get an error message such as 'Cannot Empty the Clipboard.' This is a temporary fix, but may prevent you from losing the information you want to copy and paste.
2. Go to the 'Start' menu. Click 'Run' and type 'clipbrd.exe.' Leave the window with the Clipboard open for a while. This may resolve the problem.

3. Open Task Manager. Click the 'Process' tab. Turn off the process called 'rdclip.exe.'
4. Open Microsoft Excel. Click 'Tools' and 'Options.' Click the 'Calculations' tab.
5. Under 'calculation,' check the box next to the word 'Automatic.' Restart the computer.
6. Try to clear the Clipboard. Open Clipboard and choose 'Edit.' Click 'Clear All.' Also select the 'Collect without showing Office clipboard' choice on the bottom of the window. Click 'OK,' close the window and restart the computer.

1. Back up your entire registry by either exporting it to another file name or saving it to an external device, such as a USB flash drive, external hard drive or a CD. Hopefully you won't need this, but it's better to be safe.
2. Set a system restore point in either Windows XP or Vista. This allows you to go back to a stable system that existed before you edited the registry.

3. Click on 'Start' and type 'Regedit' in the run field, or in Vista, click on 'Run' and then enter 'Regedit.' This brings up your registry editor.
4. Know specifically what you need to change. The Windows registry is huge and navigating it line-by-line is almost impossible. You can also search the registry for specific keywords related to your problem.
5. Select the area you need to edit from the left pane of the editor. Lines of code will appear in the right pane, where you are able to make your changes. Be careful not to make a mistake.
6. Save your changes. Close the editor and reboot. Any changes you made will become effective during the boot-up process.

1. Make sure that you have run your virus scan on your computer and cleared out any possible viruses or threats that your computer may have.
2. Next you will need to go to either CNET.com or malwarebytes.com and download the free malwarebytes malware removal software.

3. When the prompt pops up to run or save, click on save and select the directory you want to save it to. I always save these because you never know how long the company will supply these services for free so it is useful to save it in case you ever need to reinstall it.
4. Close all of the programs that are running on your computer such as the internet explorer except for the malwarebytes program.
5. Next you can follow the prompts on screen and install the program.
6. Once the program is installed you should run it on the full scan mode to get rid of any malware your computer may have. This should fix your problem with the internet explorer.
7. Once the scan finishes remove or delete the threats and then restart the computer.

1. Click 'Finder' on the dock to launch a new Finder window. Click 'Macintosh HD' and double-click the 'Applications' folder.
2. Double-click the 'Utilities' folder and double-click 'Terminal' to launch the Terminal.

3. Type the following command in the Terminal and press 'Enter' to disable the problem reporter feature:sudo chmod 000 /System/Library/CoreServices/Problem\ Reporter.app
4. Close the Terminal.

1. Download a program to stabilize the Windows registry. This part of the operating system governs the file associations and processes for every file format the computer encounters. When the registry becomes corrupt, MIME errors and other similar problems are more likely to present. A thorough cleaning of the registry resolves these issues in most cases. Many programs are available to address this task, including RegCure, a free download. The program should resolve MIME type errors while also making the PC more efficient and thus faster to operate.
2. Install the Windows registry optimization software. These programs are usually lightweight and install quickly and painlessly. Double-click the downloaded file and follow the onscreen instructions until the program is completely installed.

3. Run the Windows registry optimization software. Most programs offer considerable customization and features. MIME errors are just one deficiency a good registry program will fix. Choose from the available options or, for first-time users, accept the default configuration. Cleaning the registry and optimizing the PC are handled quickly by the program. All should be finished within two minutes.
4. Close the software and reboot the computer.
5. Attempt to open the downloaded file that first caused the MIME errors. In most cases, these errors should no longer appear. However, because MIME errors are sometimes caused directly by a corrupted file, it is possible the solution cannot be fixed on your end. In such a case, request a new copy of the file.

Install Important System Updates
1. Click the 'Start' button in Windows and expand the 'All Programs' folder. Click the 'Windows Update' link that appears in the first program column. This will launch Microsoft Internet Explorer.
2. Click the 'Express Install' button. Windows will begin searching for all important updates that you have yet to install, which will take a few minutes.

3. Click the 'Install Updates' button if Windows finds any important updates for your computer. The updates will begin downloading and installing immediately, but the process can take some time.
4. Reboot your computer when prompted to do so after the installation process concludes.
5. See if problems related to winhttp.dll still occur. If they do not, the updates likely fixed the problem, as updated versions of this file are included with most service pack updates for most versions of Windows. If you're still having problems, try the next section on restoring the last working version of winhttp.dll.
Restore the Last Working Version
6. Click the 'Start' button in Windows. Expand 'All Programs,' then 'Accessories' and then 'System Tools.' Click 'System Restore.'
7. Click the bubble next to 'Restore my computer to an earlier time' and then click the 'Next' button.
8. Select a restore point from the calendar by clicking on a bold date. If you just started experiencing problems suddenly, perhaps after installing conflicting software or getting a virus, choose a restore point from right before you started having problems. If you think the problem may have been there for some time, use the 'Back' button next to the calendar to scroll back to the earliest restore point. After you click a restore point, click the 'Next' button.
9. Read the restore details on the confirmation screen; then click the 'Next' or 'Finish' button. The computer will restore itself and reboot automatically, which may take several minutes.
10. Click 'OK' in the confirmation dialog box that appears after Windows starts up. See if you still have problems related to winhttp.dll. If you do, the best solution may be to replace the file manually. Find these instructions in the final section.
Replace Winhttp.dll Manually
11. Use your Web browser to navigate to a site where you can download winhttp.dll for free. You can find a link to a reliable download site in the Resources section.
12. Click the download link, save the file to your hard drive and open it. It will open in WinZip or your equivalent unzipping software. Unzip the winhttp.dll file to your desktop.
13. Double-click the 'My Computer' icon; then navigate to the system folder. If you're using Windows XP or Vista on a 64-bit system, this folder is at 'C:\Windows\SysWOW64.' If you're using either of those operating systems on a 32-bit system, the folder is at 'C:\Windows\System32.' In Windows NT and 2000, the folder is located at 'C:\WINNT\System32.' Finally, in Windows 95, 98 and Me, it's at 'C:\Windows\System.'
14. Drag the winhttp.dll file from the desktop into the system folder. If you see a prompt asking you whether or not you want to replace the existing file with the new one, click 'Yes.'
15. Restart Windows. Upon boot-up, Windows will register the new .dll file automatically, and you should be able to use Web- and network-related software normally.

1. Click on the 'Start' button and select 'Shut down.'
2. Click on 'Restart' in the Shut Down Windows dialog box. Wait till Windows boots up. If you still get error message 14, go to the next step.

3. Click on 'My Computer.' Right-click on your hard drive and select 'Properties.' You should see a pie graph of free and used memory space. If your free space is less than 10 percent, consider upgrading your hard drive with a larger memory space. Contact your manufacturer or see an authorized dealer. Do not try to open your computer if you don't have prior experience. Doing so will void your manufacturer's warranty.

1. Click 'Start,' type 'Run' in the search box in the Start menu and press 'Enter.'
2. Type 'Regsvr32 wintrust.dll' into the Run dialog box and press 'Enter.'

3. Click 'OK.'
4. Open Microsoft's Windows Installer update download page. (See Resources.)
5. Click the 'Download' link to the right of 'Windows6.0-KB942288-v2-x86.msu.'
6. Save the file to your computer by clicking 'Save' in your Web browser.
7. Double-click the downloaded 'Windows6.0-KB942288-v2-x86.msu' file on your computer.
8. Click 'Continue' in the user account control prompt window.
9. Install the update by following the instructions on your screen.
10. Uninstall SmartView normally by clicking 'Start,' clicking 'Control Panel,' clicking 'Uninstall a Program,' clicking 'SmartView' in the list, clicking 'Uninstall' and following the instructions on your screen.

Remove McAfee Using Your Control Panel
1. Click on your start button. Click on 'Control Panel.' Double click on the ' Add or Remove Programs' icon.
2. Locate and click on the McAfee SecurityCenter product (or Network Associates product). Click on the 'Remove' button.

3.

Put a checkmark against each McAfee product that you want to remove and click on the 'Remove' button. In our example, we've chosen to remove all McAfee products.
4.

Click on 'Remove' when you receive the warning message. This initiates the removal process.
5.

Let the process complete. It will show the status as each program is removed.
Download and Run the McAfee Removal Tool
6.

Close all McAfee applications windows that you may have open. Download the McAfee Removal tool (See Resources below). Click on the 'Save' button and save it to the desktop.
7. Double-click on the MCPR.exe file to launch this tool. If you use Windows Vista, then right-click on it and choose ' Run as Administrator.'
8. Once the process is complete, you will receive the message: 'Clean Up Successful.' Now re-boot your computer – this is required to fully remove the McAfee product. Once re-booted, the McAfee product will be uninstalled. (If you get the error message: Cleanup Unsuccessful, ' go to Section 3 below.)
9. Remove Leftover McAfee Folders. This is an optional step. *Click on 'Start' and then 'My Computer.' Double click 'Program Files.'*Locate any McAfee product folders that may still be listed. Right click on each one and click on 'Delete.'*Close the 'My Computer' window.
If You Get the Error Message: 'Cleanup Unsuccessful' After running McAfee Removal Tool
10. If you get the error message: Cleanup Unsuccessful, ' you will need to save the troubleshooting logs and then contact McAfee Technical Support. Follow the steps below to see how to do this.
11. In the same window with the error message above, click on ' View Logs.' In the NotePad window that opens, Click on 'File' and then on 'Save As.'
12. Save the file to your desktop. Ideally, give this file a name that includes today's date, for example: mcpr_june_15_08.txt
13. Contact McAfee Technical Support. Provide the technician this log file for troubleshooting.

1. Log in to a Windows XP with user account that has administrator credentials.
2. Click 'Start,' point to the 'All Programs' listing and then to 'Accessories.' Point to 'System Tools' and select 'System Restore.'

3. Select 'Restore My Computer To An Earlier Time' and click 'Next' to open the 'Select A Restore Point' window.
4. Select a restore point that was created before you began experiencing errors on Windows XP. Click the left arrow buttons to select an early point if you are unsure. Click 'Next.'
5. Click 'Next' in the 'Confirm Restore Point Selection' panel to begin the restore process. Your computer will restart and the utility will restore your computer to the operating condition of the restore point.

1. Click the 'Start' button. In the search box, type 'services.ms,' then click the magnifying glass icon or press the 'Enter' key. The 'Services' window appears on the screen.
2. Scroll down to and right-click the 'Print Spooler' option in the list of Windows services, then select 'Stop' on the pop-up menu. Windows halts the Print Spooler service on the computer. Click the '-' symbol in the upper right corner of the Services window to minimize it.

3. Right-click the 'Start' button, then click 'Open Windows Explorer' on the pop-up menu. Double-click the 'C:\' drive link in the folder window. Scroll down to and double-click the 'Windows' folder.
4. Navigate to the 'System32\spool\PRINTERS' sub-folder. Double-click the 'PRINTERS' sub-folder to open it.
5. Highlight all of the files in the 'PRINTERS' sub-folder, then press the 'Delete' key.
6. Click the 'Services' window link on the taskbar to maximize the window. Select the 'Print Spooler' service option, then right-click it. Click 'Start' on the pop-up menu. Close the 'Services' window. The Print Spooler service restarts.

1. Launch your Windows Live Messenger by clicking its icon on your desktop.
2. Click the 'Tools' menu on your Messenger, and click 'Options.'

3. Click 'Connection' on the left side menu within your Options menu.
4. Click 'Advanced Settings' and delete all content in the field titled 'SOCKS.'
5. Click 'OK' twice in the following prompts and attempt to open your Windows Messenger again. It should start without Error 81000306.

1. Note the process that is generating the Rundll error by examining the last file name in the error that ends in \'.dll.\'
2. Open the service configuration program on your computer by selecting the \'Start\' menu and typing \'command\' in the search text field. At the DOS prompt type \'services:msc\' and click \'Enter.\'

3. Select the DLL service from Step 1. Right click the service name followed by the \'Stop\' menu button. Exit the service configuration program.
4. Open your computer's registry editor by typing \'regedit\' at the DOS prompt and navigate to the Rundll registry key by typing \'Microsoft\\Windows\\CurrentVersion\\Run\' in the Search field.
5. Select the registry key returned and in the value associated with the registry key, confirm it ends in the same DLL file name found in Step 1. If it does, single left click the value and Press the \'Delete\' key. Exit the registry editor.
6. Restart your computer and the Rundll error will be corrected.

1. Restart your system to see if the operating system will load correctly. Depending on the type of error that was encountered, you should be able to restart your system and load the operating system.
2. Undo the last action that you did before the error occurred. If you installed a new program, go to the Control Panel and remove it under Add or Remove Windows Components. Reboot your system, and use it normally to see if the blue screen error occurs again.

3. Restart your computer using the last known good configuration option. When your computer has been restarted, press the F8 key multiple times when the computer boots up. This will display the Windows Advanced Options menu. Tab down to Last Known Good Configuration, and press Enter.
4. Run a registry cleaner to remove old and unneeded entries from the registry. You can use a program such as CCleaner or RegSeeker to clean up your registry (see Resources). Alternatively, you can use the Cleanup Center provided by Microsoft OneCare (see Resources).
5. Restore your system to a previous point before the blue screen error occurred using the Windows System Restore feature. You can access System Restore on Windows XP through the Start menu. Select Run, type 'Restore' and then click the 'OK' button. When the Restore window is displayed, double-click the rstrui.exe file. If you are running Windows Vista or Windows 7, go to the Start menu and type 'rstrui' in the search box and press the 'Enter' key.

Set Internet Explorer to Read JavaScript
1. Access Internet Explorer by opening it up on your computer. If it isn't already installed, visit the Microsoft Web site to download the latest version (see Resources below).
2. Go to 'Tools' on the task bar and click on it.

3. Select the 'Internet Options' heading.
4. Locate the tab labeled 'Advanced' and click on it.
5. Scroll through the list of settings until you see the 'Java' category.
6. Use your mouse to place a check in the box beside the only setting option under 'Java.' This setting option is 'Use JRE 1.5.0_05.'
7. Click 'OK.'
8. Re-start your computer. Your computer must be re-started in order for the change you just made to take effect.