Exchange 2010 Update Rollup failed – error 1603

If you’ve never seen this error code¬†before when installing Update Rollups for Exchange 2010, then you haven’t lived. There’s plenty of blogs and articles out there about it, but I wanted to record it for my own purposes so I don’t go trawling for the answer next time!

In a nutshell, the reason this happens is that UAC hates you.

Simple fix to this is to run CMD as Administrator, and use msiexec to install the Update Rollup, like this:

msiexec /update Exchange2010-KB2961522-x64-en.msp

Gotchas? Well the file should be on a local drive (not a network share). If you are still having problems after this, take a gander at the following KB article:

That’s about it. Happy Update Rollup’ing!