Problems upgrading from Business to Ultimate

I recently upgraded from Business(SP1) to Ultimate(SP1) (both versions
are 64 bit).
The first try "succeeded", but Windows Update would no longer work.
After trying a couple of fixes, I re did the upgrade, which seemed to
work.

Now, when I do ASP.Net development, I get the following error:
System.UnauthorizedAccessException occurred
Message: Access to the path
'C:\Windows\Microsoft.NET\Framework\v2.0.50727\Tem porary ASP.NET
Files\~AspAccessCheck_33d06fea.tmp' is denied.

When I run (32 bit)aspnet_regiis, it claims that IIS isn't installed,
and bails.
64 bit aspnet_regiis returns an unspecified exception.

Windows thinks that IIS is installed, and I can at least view static
web pages. I have the IIS 6 bits installed.

Environment
Core Duo with 2 GB of memory.
I am an administrator, but I'm not running Visual Studio as an
"Administrator."
Development Environment:Visual Studio 2008

Any Clues?

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