volume “Macintosh HD” is suddenly read only by Final Cut Pro

dcdenison wrote:

Hi, I started getting this issue on Final Cut Pro when I tried to create a new library:

"You can’t save the file “Test Library-Mac Mini.fcpbundle” because the volume “Macintosh HD” is read only. Try saving the file to another volume."

When I logged out and logged back in as a new user, it went away.

This means that settings or files in the original account might be causing the issue, according to Final Cut Support.

What settings or files should I look into?

Thank you

See if there is anything here—

Create a new library in Final Cut Pro - Apple Support

dcdenison wrote:

When I logged out and logged back in as a new user, it went away.

What do you mean "new user"? I suspect that there have been some previous events that you haven't described. I think they probably didn't work out as you had hoped.

The most likely explanation is that whatever you were doing in that "previous user" has corrupted the user account. It now only sees the read-only "Macintosh HD" volume and not the "Macintosh HD - data" volume. Apple tries to merge these two to avoid confusing people. But sometimes, people just can help themselves and they try to follow instructions they find on the Internet to do something clever. They wind up corrupting their user account or perhaps their entire system. I can't begin to guess what happened, but I think my high-level description is probably pretty accurate.