The cynic in me would ponder whether Tamron is owned by Microsoft, but let's not go there.

It could have been a slight misalignment of the lens in the mount, or a bit of something that was preventing one of the contacts from having a good connection.

If it went away after mounting the remounting the lens, and does not reappear, I wouldn't worry about it.

If it happens again with just this lens, you probably want to check the contacts and consider sending it in for service.

Mick
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