Changing content type of list item is impossible

[David_Elsner]

I have a SharePoint library with a file that must have another Content type that it should have. But changing it seems impossible.

After changing the Content type it suddenly goes back to the "Document" Content type.

See for yourself how it looks for me:

Any idea why this happens?

[#2]

I did not find this out. I had to remove the document ctype from the lib and then re-upload the file. This solved the issue.