I have just imported some pages and page types from my development server and I'm experiencing an interesting problem.
If I log into the CMS using my credentials and via the domain name from which I did the import, everything works fine and the tree loads as expected. However, when logging in with the same credentials but via a secondary domain, the tree will not load and gives the .NET error EPiServerException: Cannot find page type 94.
Page Type 94 is one of the pages I have just imported - it appears in the Page Type tab in Admin when logged in via the first domain but not in the same view when logged in through the other domain!
restart your web servers... its a caching issue. One trick is to just make a small change in the web.config
Unfortunately touching the web.config does not seem to refresh the cache for us, but the problem did right itself in the end.