Strange MiKTeX Update Error

My last MiKTeX update from 2011-07-04 failed with a strange "Permission 
denied" error for a Temp-folder without any restrictions:

update-2011-07-05-12-28.log
---------------------------
MiKTeX Update Wizard Report

Version: 2.9.4175
Date: T
Time: 1
downloading 
ftp://ftp.fu-berlin.de/tex/CTAN/systems/win32/miktex/tm/packages/miktex-zzdb2-2.9.tar.lzma...
562031 bytes, 297.65 KB/Sec
updating package definition directory 
(D:\Programme\MikTeX\tpm\packages)...
installed 2062 package definition files
visiting repository 
ftp://ftp.fu-berlin.de/tex/CTAN/systems/win32/miktex/tm/packages/...
repository type: remote package repository
loading lightweight database...
downloading 
ftp://ftp.fu-berlin.de/tex/CTAN/systems/win32/miktex/tm/packages/miktex-zzdb1-2.9.tar.lzma...
112634 bytes, 180.61 KB/Sec
starting package maintenance...
installation directory: D:\Programme\MikTeX
package repository: 
ftp://ftp.fu-berlin.de/tex/CTAN/systems/win32/miktex/tm/packages/
lightweight database digest: 9d6858b8490e357d4f00f6bcbe53d279
going to download 3566244 bytes
going to install 87 file(s) (2 package(s))
downloading 
ftp://ftp.fu-berlin.de/tex/CTAN/systems/win32/miktex/tm/packages/dehyph-exptl.tar.lzma...

Error: Permission denied: C:\DOCUME~1\theis\LOCALS~1\Temp\mik5.tmp
-----------------

I have no idea, why the MiKTeX updater could not write onto the file 
mik5.tmp. I repeated the update-procedure by starting MiKTeX update from 
surun, giving it administrative rights, without success.

MiKTeX 2.9 has been installed for the (normal) user "theis" and runs 
smoothly under Windows XP Professional.


Werner
-- 
W. Theis
ITP Hannover


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