What could be reasons a WPF app would pin the CPU and lock the app on some computers but not others?

Question

Stumped here. Posted a similar question before. We have a pretty large WPF app that on some machines runs great, but on others, all of a sudden, one of the CPU cores gets

Answer 1

Found it!! Turns out there's a bug in .NET 4.0 regarding UI Automation and the changes MS introduced. Here's the info, and the fix! (Note: Even if you call MS, they will send you a link, but it's always a broken link. I managed to track this down manually.)

Note: Their article talks about a specific case that causes this behavior, but if you google around, you'll see tons of issues around hangs related to those DLLs. The latest is they're promising a fix in the .NET 4.5 runtime (from a MS post on this issue.)

Here's the KB article...
http://support.microsoft.com/kb/2484841/en-us

...and here is the actual hotfix.
http://archive.msdn.microsoft.com/KB2484841/Release/ProjectReleases.aspx?ReleaseId=5583