What is your operating system, 7 RC or 7 fnal ? RC can be the problem.
NIS 2010 could have disabed Windows Defender and stopped its service. Uninstalling NIS did not necessarily turn the service back on.
1. Make sure that Windows Defender service is running:
Control Panel -> Administrative -> Services
2. Try system restore.
3. Updae your system.
4. If nothing helps, reinstall Windows Defender:
1) Click Start, Control Panel.
2) Click Add or Remove Programs.
3) Click Windows Defender, and click Remove.
This will uninstall Windows Defender. You can download and reinstall the updated version from the following link:
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