MiKTeX Setup 2.9.4217 fails with Permission denied error on Win 7 32 bit

Hi everybody,
I tried different types of the latest MiKTeX 2.9 setup on my Win 7 32 bit system (Basic, Complete, Net Install), but all fail with the following error message when the setup loads the package database:
------------------------------------------------------------
MiKTeX Setup 2.9.4217 Report

Date: Sunday, July 24, 2011
Time: 18:04:58
OS version: Microsoft Windows 7 Business Edition, 32-bit Service Pack 1 (build 7601)
SystemAdmin: yes
PowerUser: false
SharedSetup: yes
Setup path: C:\Users\Stephan\Downloads\MikTex29\setup-2.9.4217.exe
UserRoots: <none specified>
UserData: <none specified>
UserConfig: <none specified>
CommonRoots: <none specified>
CommonData: <none specified>
CommonConfig: <none specified>

Installation: C:\Program Files\MiKTeX 2.9 Loading package database...

An error occurred:
  source file: Libraries\MiKTeX\Core\win\winFile.cpp
  source line: 686
  message: Permission denied: C:\Users\Stephan\AppData\Local\Temp\mik16040\fmp.tpm
  info: C:\Users\Stephan\AppData\Local\Temp\mik16040\fmp.tpm

------------------------------------------------------------

What I tried so far without success:
- Gave "Everyone" full permissions on the Temp Directory
- Run the setup in XP compatibility mode
- Specified "Run as Administrator"

I used the 64bit installer on my 64bit machine without problems. Any solution known to this problem? 

Cheers,
Stephan



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