The 10 common Windows security vulnerabilities

The 10 most common Windows security vulnerabilities
Here's my top 10 list:

1. File and share permissions that give up everything to everyone.
2. Lack of malware protection
3. Lack of personal firewall protection.
4. Weak or nonexistent drive encryption.
5. No minimum security standard.
6. Missing patches in Windows as well as third-party software,such as VNC, RealPlayer and others
7. Weak Windows security policy settings.
8. Unaccounted for systems running unknown, and unmanaged, services such as IIS and SQL Server Express.
9. Weak or nonexistent passwords.
10. Windows Mobile and other mobile device weaknesses.

Tools to find these vulnerabilities
There are many good tools, including port scanners and system enumeration such as.
1. SuperScan
2. QualysGuard
3. OmniPeek
4. CommView
5. Hex editor

Source
http://searchenterprisedesktop.techtarget.com/tip/0,289483,sid192_gci1331487,00.html