Fixing with Anti-Virus
1. Shut down the computer.
2. Restart the computer, but press F8 repeatedly to bring up a menu asking how you'd like to boot the computer. Select 'Safe Mode.'

3. Open the anti-virus software on your computer. If you don't currently have one, you can download a free one from the link provided below (see Resources).
4. Perform a full system scan. Being in safe mode will allow the scan to detect and remove more infected objects.
5. Click 'Remove' once the scan is complete.
Fixing the Registry
6. Download the RegCure software through the second link in Resources. This software will scan the computer for all possible registry errors and issues.
7. Double-click the RegCure download icon, then follow the steps to complete the installation.
8. Open RegCure by double-clicking the new desktop icon.
9. Click 'Scan', leaving all of the scan options selected.
10. Click 'Remove' once the scan is complete. Once this step had been performed, there should no longer be any more lsass.exe system errors