:: Can anyone tell me what the error 0x643 means?
Can you tell us what you're trying to install and on what OS etc?
My guess, is a Framework update :
When you try to install an update for the .NET Framework 1.0, 1.1, 2.0, 3.0,
or 3.5, you may receive Windows Update error code "0x643" or Windows
Installer error code "1603"
TaurArian [MVP] 2005-2009 - Update Services
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