Every once in a while – and by that, I mean ALL. THE. TIME. – I run into a situation where a number that I’ve been asked to provision as a LineURI for a SfB endpoint is already in use:

“Filter failed to return unique result” has got to be one of the most frustrating errors that you can receive. At least it doesn’t tell you to contact your system administrator…

Sometimes this is easy to figure out by searching for that number in the User Search section of the Control Panel:

And other times it’s not, because the number is hiding, assigned to one of the following:

• User LineURI
• User PrivateLine
• CsAnalogDevice
• CsCommonAreaPhone
• CsExUmContact
• CsDialInConferencingAccessNumber
• CsTrustedApplicationEndpoint
• CsRgsWorkflow
• CsMeetingRoom LineURI
• CsMeetingRoom PrivateLine

And you know what you don’t want to do? You don’t to have to dig out PowerShell and search all of these manually. What you need is a script to do this for you, and while there are a couple out there, the one by Lasse Wedø is my favorite.

It’s comprehensive, well-written, has nicely formatted output, and has a tonne of parameters available if you want to do a more complex search. The simplest form of search looks like this:

which seems just about right to me. Download the script and give it a try next time you run into duplicate number issues.