Failed to find a DDI

Hello!

When launching/debugging on my iPad and iPhone I keep getting the following error:

“Previous preparation error: Failed to find a DDI … Run ‘devicectl list preferredDDI’ …”

I believe this was caused by a previously interrupted Xcode update around June due to low disk space, which may have left DeviceSupport/DDI/CoreDevice files incomplete. Even after finishing the update later, the error persists. I now use a new Mac with 4 TB of storage, but the issue still occurs.

Since then I have unfortunately been blocked from testing or presenting my app on devices. It seems that only a new, fully completed Xcode update might resolve the problem.

Tried so far: – Cleared caches (CoreDevice/Devices) – Reset trust on device and re-paired – Checked devicectl list preferredDDI

I would really appreciate guidance, as at the moment I cannot present my app due to this blocking issue.

Thank you very much for your support!

Can you provide the output of devicectl list preferredDDI?

— Ed Ford,  DTS Engineer

Hi Ed, thanks for the quick reply. I tried to reply directly in the forum with the requested output, but I keep receiving an error message ("Your post couldn’t be saved. Please try again in a few minutes."). It seems I cannot currently post a follow-up reply. The output: zsh: command not found: devicectl

I got this reply. 😀

I underspecified the exact command there, which is my mistake. The full command is xcrun devicectl list preferredDDI. What's that output?

— Ed Ford,  DTS Engineer

Failed to find a DDI
 
 
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