Logic Pro: Intermittent OSStatus error -50 with built-in instruments

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Level 1

4 points

Logic Pro: Intermittent OSStatus error -50 with built-in instruments

I’m intermittently getting the following error in Logic Pro:

“The operation couldn’t be completed. (OSStatus error -50.)”

This particular error occurs when I’m using or selecting Logic’s own built-in instruments/sounds, so it does not appear to be limited to third-party plug-ins.

The difficult part is that I haven’t been able to find a consistent way to reproduce it. Sometimes everything works normally, and other times the error suddenly appears while working in a project.

Has anyone encountered OSStatus error -50 specifically when using Logic’s native instruments or sounds? If so, were you able to determine what was causing it or find a solution?

I’ve attached a photo of the exact error message.

I am on Mac OS 15.7.3, Logic 12.3, using Universal Audio Apollo Twin interface, and using external drives to house my logic projects, and music libraries.

Mac Studio, macOS 15.7

Posted on Aug 12, 2026 12:59 PM

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Answer 1

JGaddy92

Level 1

8 points

Aug 12, 2026 4:17 PM in response to ddevor

I think this happens when you have the plug-in setting slot selected in the inspector and try to load a patch from the library. Normally it switches what’s shown in the library based on which slot has focus. But sometimes it doesn’t. Try selecting the top slot of the channel strip when this happens and load the patch. Should work.

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