Cannot vote on answer unless edited because it is locked

Question

I tried to vote on the other answer to my question, but it says I can’t unless it is edited because my “vote” from 45 minutes ago is locked. The only vote on that answer was from well over a week ago and neither arrow next to the answer is highlighted.

Answer 1

You have a 5 minute window to cast and uncast votes; after the first vote is cast, the clock starts ticking.

Regardless of the final state, the clock starts ticking the second you click a vote arrow.

This is to prevent many kinds of vote undo exploits.

Answer 2

I see only 1 upvote on harrymc's answer from the timeline. This plus you indicate that you're getting a message about vote being locked makes me believe this might have happened:

• Clicked on the upvote
• (Accidentally?) clicked on the upvote again, hence "cancelling" it. The system still sees it as a vote - after all you did vote on it. The vote is now locked.

I can simulate the same -

Voted for your answer

Now cancelled my vote. There's no sign of the upvote and it's locked in till the post gets edited.

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