Endpoint Protection

We just upgraded one of our clients to SEP 11.06a no problems with install, most clients installed just fine with no issues, but 2 our of 16 are experiencing huge slow down after the install. Network seems to be up, but IE8 will not open, Chrome, PCAW, and Outlook their main applications do not function, and their system is slow on startup. We just install the Antivirus part of SEP 11.06a I did not install the Firewall, or Network Scanning part of SEP, only way to get them to speed back up is to run the uninstall of SEP and wait it gets to a point during uninstall where it just stops still shows a countdown which is 0 seconds and the bar stops moving but no notifications or anything. We have to hard boot the PC because it will not actually shut down by start shutdown.
Ok, so here are their specs. XP SP3 Patched as of 6/15/2010, 2.66Ghz, 2GB RAM, Office 2003, previous SAV 10.02 (Ran NoNav 2.611 after first SEP Failure still no luck), Windows Firewall Is Running on all Workstations.

First off, don't use NoNav for SEP. It's not designed for SEP and won't remove SEP properly. We have a utility called Cleanwipe that may be used when an uninstallation fails. It automates the uninstallation process.

I think this doc will point you in the right direction...
http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2008042314291548

hi there,

you get CleanWipe utility version 6 from TechSupport. This tool is cool to remove SEP from the system. By the way this tool is not supported by Symantec though and you need to run it at your risk. But it works 99% most of the time.

So I ran through the Manual Uninstall once before with no luck, it has never really been about removing the program, that only becomes a problem after it has been installed and it starts locking up IE and Outlook. I ran NoNAV to get rid of anything that might be lingering from the previous version of SAV 10.2.

I already tried the Microsoft CleanUp Utility with no luck, it appears like SEP 11.06 is actually completely removed, it does not try to start up or run any services after the uninstall, it just gets locked up during the uninstall, it does seem to finish, just does not tell you its finished (If that makes any sense, I feel like I am talking in circles) 

Anyway, if the Cleanwipe utility will help I would be willing to give it a try as I have not tried that yet.
Since I did not install any of the Network Protection side of SEP just the AV, does it still sound like a bad install of SEP? I have installed this on many of the machines in this office which are all configured pretty much the same with no issues.