error 1719 the windows installer service could not acc

My trouble is related to new beta 2 of Vista, and in facts is the same reported by that page:
http://support.microsoft.com/default.aspx?scid=kb;en-us;315346
but related to Vista OS.
how can I properly re-register or reinstall windows installer on Vista?
my Vista is a x64 OS beta 2
my pc:
Athlon 64 3200 +
2 GB ram ddr
geforce 6600 GT with latest NVIDIA Vista driver
creative audigy 2 platinum (still without a driver installed)
Vista hd partition: 42 GB on a SATA maxtor 152 GB drive

I installed some windows 32 bit applications, like spybot SD
http://www.spybot.com/
but after some successfull run they doesn't work anymore, prompting always this error message:
"this application has failed to start because ole32.dll was not found. Re-installing the application may fix this problem"
but in facts, when I try to reinstall the application, the system prompt me the error related to windows installer corrupt installation -.-