Exchange 2007 SP1 Update Rollup 4 was released on Microsoft Update, a question came up: how do you tell which version of the Update Rollup is installed? The simplest answer is to go to Add or Remove Programs Control Panel applet. Then:

1. Make sure that "Show updates" checkbox is checked
2. Click on the Update Rollup that you are trying to figure out version information for
3. Click on the "Click here for support information" link