I ran across a strange error today for the first time installing the SharePoint bits on a new server.  Basically I was using the MSDN package which contains SharePoint Server 2010 SP1 – build 759775.  I was installing it on a Windows 2008 R2 Server with SP1 installed.

Problem

Normally SharePoint’s pre-requisite installer installs everything flawlessly.  However, today, it failed trying to install KB976462 – the Hotfix for Microsoft Windows.  The error message wasn’t particularly helpful – just a failed to install error –  Install process returned (-2145124329) as seen in the below image:

After spending of course too much time searching for a fix, I finally ran across this KB article:

http://support.microsoft.com/kb/2581903

Basically, the bottom line is that Windows 2008 R2 Server SP1 already has that Hotfix included in the service pack, so the SharePoint Prerequisite installer is failing on an attempt to install it.

Fix

The fix is simple – just Run the SharePoint PreRequisite Installer again, and it will detect that KB976462 is installed, skip it, and install all the rest of the prerequisites.

Results look like this – much better:

Questions

Of course this brings up as many questions as it answers:

1.  Why can’t the SharePoint PreReq installer recognize the Hotfix is already installed on the first pass, but can recognize this on the second pass?

2.  Will Microsoft fix this?  Patch the PreReq installer in a future CU or SP?

3.  Shouldn’t standard error trapping in software not prevent all the downstream steps in a process from happening?

3.  Why, why, why?

But, such is life in technology.