One of the more confusing things about the QFE sets Microsoft releases is that the KB articles specifically say to only apply patches if you are experiencing the issues, however in an environment like OCS if you patch some components, others will not work.
After applying the July round of updates to our internal environment users were no longer able to authenticate to PSTN dial in conferences using their extensions and pin numbers. If the user signed into CWA to check this information they would see this message:
I poked around a bit and noticed one thing that was changed from before I applied the updates, this was not the root cause of the issue but may be something to look out for, my conferencing region was assigned to the wrong location profile, prior to these updates it was assigned to the correct location profile:
As you can guess that is a testing location profile with the number 2 on the end.
The root cause of the issue was actually related to the below error message which I was receiving on the EE Front End Server:
Error 8/22/2009 7:40:41 AM OCS UserPin Service 47019 (1044)
This pointed to a database issue, I reviewed the July updates and noticed I had not applied the backend database hotfix, I promptly installed the SQL 2005 Client tools on my front end server and ran this Command to install the July backend database update.
Once I installed this update I was able to connect to my CWA server and view my correct dial in information, as well as authenticate with conferencing bridges via PSTN.
I guess it is just important to note that you should install all updates associated with a QFE release or it is possible to run into issues like this.