QR Code Troubleshooting
Something is not working. These pages diagnose rather than list: each failure was reproduced with the real encoder so the advice points in the right direction.
The most useful thing to know up front is that some failures cannot be fixed. If a logo covers 40% of a code, the data underneath is gone and no scanner recovers it.
Check the Code Itself First
Before changing anything, read what your code actually contains with the image reader. A surprising share of "not scanning" turns out to be a code that scans perfectly and points somewhere dead, which is a different problem with a different fix.
Guides worth reading
- TroubleshootingScanning from a screenshotThe file route on each device, what a chat app does to the image on the way to you, and why failing once is worth retrying at a different size.
- TroubleshootingWhy a QR code will not scanEach cause reproduced with the real encoder and read back, ordered by how little slack it gives you.