One of our users create a private repository within and organisation on GitHub Enterprise. He added a collaborator, but this person get 404 error when trying to access the repo. I added my account to this repo and all works fine for me.
Added collaborator is in the same organisation, repo is visible on his profile, link to repo is fine too (it works for me and repo owner).
I was searching the answer in Internet, but no luck.
Do you have any idea, what can cause this situation?