License is forgotten, mp3tag reverts to trial after starting

After using mp3tag without any problems for years, recently it started asking for my license every time I start the app. When I input the serial, I get a message my copy is now licensed, but the next time I start the app, mp3tag is in trial mode again.

I’m running MacOS Big Sur (11.7). Maybe it has something to do with the recent update to 11.7.11?

It works fine on my other Mac running MacOS 26, latest version.

Have you changed anything with the permissions for files inside of ~/Library, e.g., restored something from a backup or copied from another Mac?

It sounds like the changes to Mp3tag's configuration settings are not persisted across re-runs of the app.

Not that I’m aware of. I have not restored anything, or copied any system files. I have 4 days of my trial left, so something must have happened 10 days ago (right….?), and the last big thing I did, was install the 11.7.11 security fix. Which must have been 10 days ago.

Maybe the update changed some permissions?

It's a 7-day trial and only days you're using the app are counted.

Can you run the following commands in Terminal.app and copy the output?

id
ls -ld ~/Library/Containers/app.mp3tag.Mp3tag
ls -l  ~/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences
plutil -lint ~/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences/app.mp3tag.Mp3tag.plist

Hope I did it correctly. Here’s the 4 commands with their output:



id

uid=501(Macmos) gid=20(staff) groups=20(staff),12(everyone),61(localaccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),701(com.apple.sharepoint.group.1),33(_appstore),100(_lpoperator),204(_developer),250(_analyticsusers),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh),400(com.apple.access_remote_ae),702(com.apple.sharepoint.group.2)

--

ls -ld ~/Library/Containers/app.mp3tag.Mp3tag

drwx------@ 6 Macmos  staff  192 Feb  8 19:49 /Users/Macmos/Library/Containers/app.mp3tag.Mp3tag

--

ls -l  ~/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences

total 0
lrwxr-xr-x  1 Macmos  staff  51 Dec 27  2020 com.apple.security.plist -> ../../../../../Preferences/com.apple.security.plist
lrwxr-xr-x  1 Macmos  staff  58 Dec 27  2020 com.apple.security_common.plist -> ../../../../../Preferences/com.apple.security_common.plist

--

plutil -lint ~/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences/app.mp3tag.Mp3tag.plist

/Users/Macmos/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences/app.mp3tag.Mp3tag.plist: file does not exist or is not readable or is not a regular file (Error Domain=NSCocoaErrorDomain Code=256 "The file “app.mp3tag.Mp3tag.plist” couldn’t be opened." UserInfo={NSFilePath=/Users/Macmos/Library/Containers/app.mp3tag.Mp3tag/Data/Library/Preferences/app.mp3tag.Mp3tag.plist, NSUnderlyingError=0x7fbd3dc0b3a0 {Error Domain=NSPOSIXErrorDomain Code=92 "Illegal byte sequence"}})


Yes, thank you, and the error in the last line looks suspicious.

Now please run

defaults read app.mp3tag.Mp3tag 2>&1 | head -n 40

If it produces an error, you can try with Mp3tag closed

mv ~/Library/Containers/app.mp3tag.Mp3tag ~/Desktop/app.mp3tag.Mp3tag.container.backup

and restart Mp3tag.

I got an error indeed with the first command, closed mp3tag, ran the other command, started mp3tag, entered my serial, restarted, and now it seems to work fine.

Let’s see if it stays like this the next few days, but for now thanks a lot! Amazing how fast you were able to help.

Excellent, glad it's working now!

You can now also safely remove the folder app.mp3tag.Mp3tag.container.backup from your Desktop.