I just had an issue at a customer’s site where the ConfigMgr Application Catalogs would complain. Here’s the quick and easy solution to it.
Server Error in ‘/CMApplicationCatalog’ Application
This customer does quite a lot of customisation on their servers. Granting permissions, taking them away, redirecting folders from here to there.
They for example redirect the system temp to C:\temp and take away all the permissions the user ‘Local Service’ has to that temp directory.
As soon as I added ‘Local Service’ again with full permissions, all was fine and the ConfigMgr Application Catalog started up again.