Objective-c – UUID mismatch detected with the loaded library


I get a "UUID mismatch" warning at the console when I try to build and run my app on my iPhone.

warning: UUID mismatch detected with
the loaded library – on disk is:

Anyone has this issue and managed to resolve the warning ?

Best Solution

Uninstalling and reinstalling both the iOS on the device and the SDK did not fix this for me. The only way I was able to get around this issue was by deleting the DeviceSupport files for the 4.2.1 iOS version, which can be found at:


After deleting the files and restarting Xcode, I plugged in my device and was prompted to restore the symbol files from the device itself - it took about 5 minutes and after this, everything was back to working perfectly.

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