Did you manually download/install all .NET Framework versions and SPs that
you removed?

If no joy, see this recent post by my colleague MowGreen:
http://groups.google.com/group/micro...76de7769d04493
--
~Robear Dyer (PA Bear)
MS MVP-IE, Mail, Security, Windows Desktop Experience - since 2002
AumHa VSOP & Admin http://aumha.net
DTS-L http://dts-l.net/



Carnage_7 wrote:
> I checked out that KB923100 and applied the fixes listed-still no deal.
> What next?
>
> Frank
>
> "PA Bear" wrote:
>
>> Michael, do you see *any* other threads here about the same problem??
>>
>> When you try to install an update for the .NET Framework 1.0, 1.1, or
>> 2.0,
>> you may receive Windows Update error code "0x643" or Windows Installer
>> error code "1603":
>> http://support.microsoft.com/kb/923100
>> --
>> ~Robear Dyer (PA Bear)
>> MS MVP-Windows (IE, OE, Security, Shell/User)
>> AumHa VSOP & Admin http://aumha.net
>> DTS-L.ORG http://66.39.69.143/
>>
>>
>> Michael McCrea wrote:
>>> I upgraded my Compaq Laptop XP Home to Vista Business. All my other
>>> updates
>>> will install fine but a Security Update for .NET SP 1 keeps failing. I
>>> also
>>> get an "error code 643". I attempted the fix suggested for this by
>>> turning
>>> on Services for Office Sourse Engine to "Automatic" instead of manual,
>>> but
>>> that still has not worked any suggestions