looks like avast was the issue, any idea why its doing that when C:TEMP is not my temp dir?
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Strange that as avast.setup doesn't create a C:\Temp folder on my system, that's why it threw me as my environment variables are the default, I never changed them on this new system.
Though there is an _avast4_ folder in the usual Docs&Settings area, C:\Documents and Settings\UserName\Local Settings\Temp\_avast4_. So perhaps that stops it creating the C:\Temp folder.
Good that Alan has remember the way to set it to a location of your choice.
Edit: Note you will need to disable the avast self-defence module in Program Settings, Troubleshooting, to be able to edit the avast registry keys. Don't forget to enable it after you are done, assuming you decide to go that way.