Endpoint Protection Small Business Edition

I'm trying to do a remote install of SEP 11.05 to a Windows 7 32-bit PC using the Migration and Deployment Wizard. 

It fails with the error "Unable to copy file C:\DOCUME~1\....\vprxx.tmp -  Access is denied". 

Searching the KB, this matches a similar error condition with "The network path was not found" instead of "Access is denied" . Both the C$ and the Admin$ shares were previously present and didn't need to be created.

As an experiment, I've tried giving the SYSTEM user full control over the C:\Temp directory on the target machine.  This allows the remote installation to succeed (although Windows 7 gives notification that a program wants to display a message, the program being the MSI installation file, which may be its normal behaviour) - but this required changing security on the target machine, which sounds impractical if there are hundreds of target machines.  I'm also not sure what the consequences are of giving SYSTEM full control over c:\temp.

Comments?

 User Access Control Needs to be disabled.

Windows 7 and Vista have identical Architecture so follow this
http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007091021513648

Would rather not disable UAC.  Reading the KB article, it implies that the problem shouldn't occur if the login is as a domain administrator - but that's exactly what we do, and remote install is still denied.

 To find the root-Cause disable UAC one 1 PC try deployment see how it goes .Then turn the UAC back ON.