AnyConnect 3.1 crashes on XP SP3

[tpattgeek]

We just upgraded our AnyConnect clients to the lastest 3.1 and some XP users were having issues.  One PC was able to upgrade to SP3 and it resolved the issue.  However, we still have several PC's on XP SP3 and are able to install the client manually, but when you go to connect, it sits at Posture Assessment: Initiating... and eventually gives you "Cisco Scaner has encountered a problem and needs to close".  It may also give you the same error with other applications that were already running on the PC. What should our first steps be?  If we try to connect in any browser, it gives the same error with cscan.exe.

[tpattgeek]

Update: I was able to recreate the issue on an XP VM and it fails with "Prelogon policy failed!" 

Access Denied

Your system failed to be validated by  the Cisco Secure Desktop and will not be granted access.

I was able to get in once on the website and the client alone, and it worked.  I closed my browsers, opened both of them, and now they're both getting the same Critical failure along with a Cisco Scanner encountered a problem message in Internet Explorer.  I checked my prelogon policy and it's just an OS check with XP/2k/Vista/7 being allowed so I'm not sure why every XP machine is failing the check.

[tpattgeek]

OK, the issue is with some corrupt services or software on the XP machines.  We disabled Symanted AV (which everyone in the company uses with no problem) and while host scan is scanning, Windows Explorer crashes and restarts, then the login box appears.  That is hardly a workaround so we will likely be replacing the PC's or reimaging them soon.