windows installer 100% CPU for 3 hours and fails

I am posting here because windows installer is part of windows server.

I tried to install SP1 for Visual Studio 2005. CPU is 100% all the time. It
takes about 30 to 45 minutes untill the installer shows the License
agreemend dialog.

I click [OK] then it indicates "Gathering required information". CPU is 100%
all the time. Now it takes about 2 hours to fill the progress.

Then it indicates 5 minutes remaining and about 30 seconds later it shows
this error:

[Visual Studio 255 Professional Edition - ENU]

Error 1718.File D:\WINDOWS\Installer\1597292.msp did not pass the digital
signature check. For more information about a possible resolution for this
problem, see

http://go.microsoft.com/fwlink/?LinkId=73863

2006-12-07 09:44 PM 477 190 144 1597292.msp

MD5: c0f76019179ed25d23fa2bae65357367

SHA1: 55f0c81c1010d332a89db84e5ef5e3170a826afc

I followed the link, and modified the registry, stopping the Windows
Installer service as written.

3 hours after running the SP1 installer it ended with the same error. What
should I do?

I believe that there me some bug either in windows installer or in the
service pack 1 packege for Visual Studio, because msiexec.exe uses 100 CPU
all the time (once msiexec.exe running as Local Administrator will use 100%
then msiexec.exe running as NT Authority\System will use 100% CPU). Could it
be a tread is stuck looping?