We've not experienced any issues with VPN. I've got 4202 on my laptop (the only workstation/laptop deployment of 4202 in our organization), and I have no issues with any of the Cisco VPN clients.
Our problem right now is isolated to servers with Broadcom network cards that are teamed, running 4202 with or without network threat protection enabled. However, the same symptoms occur...network cards in the machine are all fine, no access to the management server, upon reboot everything is fine, one CPU core completely maxed out. Cleanwipe actually doesn't fix it. Issue comes back after arbitrary amount of time after reboot.
Currently I'm going through this document:
http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007073018014248
And trying to see if that makes a difference.
FYI, after running cleanwipe, to get the results from the link above, do the following (this is the stuff that cleanwipe doesn't do):
Delete the following 4 registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ESENT\Process\ccSvcHst
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RFC1156Agent
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\SyKnAppS
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Symantec AntiVirus
Optional:
* Browse to the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\FltMgr
* Change the "AttachWhenLoaded" value to 0 (zero)
Browse to the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\RasMan\PPP\EAP\13 and delete the following values in the right pane:
o ConfigUiPath
o IdentityPath
o InteractiveUIPath
o Path
# Now rename and remove the "Backup" portion from the following values so that the values match those deleted from the preceding step.
o ConfigUiPathBackup
o IdentityPathBackup
o InteractiveUIPathBackup
o PathBackup
Note: If the "Backup" entries do not exist, please re-create the appropriate values as follows (the values are of type Expandable String Value):
ConfigUiPath = %SystemRoot%\system32\rastls.dll
IdentityPath = %SystemRoot%\system32\rastls.dll
InteractiveUIPath = %SystemRoot%\system32\rastls.dl
Path = %SystemRoot%\system32\rastls.dll
# Browse to the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\RasMan\PPP\EAP\25 and delete the following values in the right pane:
o ConfigUiPath
o IdentityPath
o InteractiveUIPath
o Path
# Now rename the following files by removing the "Backup" portion from the name so that the values match those deleted from the preceding step.
o ConfigUiPathBackup
o IdentityPathBackup
o InteractiveUIPathBackup
o PathBackup
Note: If the "Backup" entries do not exist, please re-create the appropriate values as follows (the values are of type Expandable String Value):
ConfigUiPath = %SystemRoot%\system32\rastls.dll
IdentityPath = %SystemRoot%\system32\rastls.dll
InteractiveUIPath = %SystemRoot%\system32\rastls.dll
Path = %SystemRoot%\system32\rastls.dll
Hope this helps.