Mastodon server admins or other experts: What could potentially cause another instance to get a 401 error when attempting to POST to my instance's inbox?
The other instance was offline for a while, and I had subsequently "Purged" it using the option in the "Moderation/Federation" admin screen to try and correct this problem. It didn't work. The other instance seems to be federating normally with other instances -- just not mine.
Any ideas?