Thanks, everyone.

So sorry for the super-late reply. But the issue was a disabled user as suggested. I noticed it again today, which is how I came back to this thread. Dropping the db user and re-mapping the login fixed the issue.

About the possible bug - this database was not the last checked db in the list, so I didn't see that pattern. But it's possible that it is a bug nevertheless, and that in some cases affects the last db in a list. I'd love to see whether anyone else sees this problem and has any clues about what causes it. My best guess right now is that it may be a side-effect of restoring a db on a different server, but that's just a hunch.

Thanks again!

- webrunner