Update Windows
1. Click on the 'Start' menu.
2. Type 'Update' into the 'Search Programs and Files' box and select 'Windows Update' from the list of results. If you are using a version of Windows prior to Windows Vista, click on 'All Programs' and then 'Windows Update.'

3. Click 'Check for Updates' in the left pane.
4. Check the box next to each available update and click 'OK.'
5. Click 'Install Updates.'
Reinstall The DLL
6. Hold down the Windows key and press 'R.' Or, if using a version of Windows prior to Vista, Click on the 'Start' menu, and then click 'Run.' (See http://www.delphifaq.com/faq/windows_user/f668.shtml)
7. Type 'regsvr32.exe /u ntdll.dll' (without the quotation marks) into the Command Prompt and press ENTER. This will uninstall the file. (See http://www.delphifaq.com/faq/windows_user/f668.shtml)
8. Type 'regsvr32.exe ntdll.dll' (without the quotation marks) into the Command Prompt and Press ENTER. This will reinstall the file. (See http://www.delphifaq.com/faq/windows_user/f668.shtml)