NAV 2009 has several problems with Windows 7 Release Candidate Build 7100 that did not occur with the Windows 7 beta Build 7000. (1) During NAV 2009 installation (version 16.5.0.134) , the Windows "Program Compatibility Assistant" window opens saying the Symantec Heuristics Driver is blocked due to compatibility issues. The check for solutions online button finds no solution. (2) Each time I launch NAV 2009, the Windows "Program Compatibility Assistant" window opens saying "This program has known compatibility issues". The Program is listed as Norton 360. The path listed is C:\Program Files\Norton AntiVirus\Engine\16.5.0.134\uiStub.exe. I can click the Run Program button and it launches. (3) After 2-3 minutes a Norton AntiVirus window opens that says "SONAR Advanced Protection failed to load" with "3039,1" in the lower left. (4) After launching NAV 2009, it takes 2-3 minutes for the Settings window to open under either Computer or Internet. The only Symantec solution linked to these issues was to use the Norton Removal Tool which I did, but without success - the same issues return. It looks like Symantec lost a lot of ground since Build 7000 and the above may only be the tip of the iceberg. One positive note - NAV Auto Protect does detect and block the Eicar Malware Test File. This applies to the 32-bit version of Windows 7. I did a clean install on a blank hard drive.