Vista - "installer has stopped working" message

I am building a test sytem to evaluate Virtual Server. The host is Windows
Vista x64 with a 2.13GHz proc and 2Gb ram and SP1 with all updates and AV
installed.

No matter what I do to install Virtual Server I get the same message
"Windows(R) installer has stopped working. The Event Log has an Event ID:
1000 with the text:
--------------------------------------------------
Faulting application MsiExec.exe, version 4.0.6001.18000, time stamp
0x47919539, faulting module MSI891F.tmp, version 1.1.603.0, time stamp
0x4655ff0c, exception code 0xc000000d, fault offset 0x0000000000002b2c,
process id 0x129c, application start time 0x01c98fb65b3fae85.
--------------------------------------------------

Despite this when I close the error message the installation dialogue
reports the application has installed succesfully. If I accept this and try
to install the two required updates these produce the same results. This also
occurs if I turn off UAC and AV.

I have wiped down the PC and redone this twice now with the same result,
what am I doing wrong?