Developer solves sudden GitHub SSH key rejection with a .pub file fix

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A developer recently encountered an unexpected SSH key rejection on GitHub that blocked access to their repositories. The issue, shared on a personal blog on July 21, 2026, puzzled the user as no obvious changes had been made to their setup. After troubleshooting, the fix turned out to involve the public key file with a .pub extension. The post gained traction on Hacker News, prompting brief community discussion around the surprisingly simple resolution.

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