Checklists for software errors, setup, and tool workflows.

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How to Manually Remove a Stuck Git index.lock File

If Git operations suddenly fail with an error like fatal: Unable to create 'path/.git/i...

How to Fix Git Unrelated Histories Error When Merging Branches
You try to merge two branches, and Git stops with: fatal: refusing to merge unrelated histo...

Fix Windows Defender Real-Time Protection Permission Denied
When you try to turn on or off Windows Defender real-time protection, you might see a "Permis...

Fix Cloudflare Origin Certificate with Let's Encrypt
If your origin server is rejecting the Cloudflare origin certificate—perhaps because of a SAN mis...

Fix Chrome Black Screen During Videos: Hardware Acceleration
If you're watching a video in Chrome and the screen goes black (but audio continues), hardwar...

Fix Nginx Upstream Connection Refused in Proxy Pass
When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Checklists for software errors, setup, and tool workflows.

Latest checklists

How to Manually Remove a Stuck Git index.lock File

How to Fix Git Unrelated Histories Error When Merging Branches

Fix Windows Defender Real-Time Protection Permission Denied

Fix Cloudflare Origin Certificate with Let's Encrypt

Fix Chrome Black Screen During Videos: Hardware Acceleration

Fix Nginx Upstream Connection Refused in Proxy Pass

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