Moving from S10 to S21 Galaxy. . . First tried using Smart Switch (copy apps) to get SM (Samsung Music) from the S10 over to the S21. Every single app on the S10 shows up *except* Samsung Music, and app transfer worked fine on other selected apps. Tried many times, so that was a dead end.
Tried doing an export in the setup menu of SM on the S10. It created several m3u files with names corresponding to the playlist names. File sizes differ according to the number of items in them, so it looked like they did contain data. Moved them to the S21
From the S21's SM setup menu, did an import. It displayed the m3u file names, acted like it did the import and displayed the playlist names. Each of them shows 0 tracks and are empty when selected in SM.
I manually installed SM on the S21. Are there playlist files I can manually move from the S10 to the S21 since the export/import function doesn't work?
Try using smart switch to make a complete backup of your phone to snexternal fladh drive or computer, then restoring the complete backup to your new device. Does the music library transfer but the app and created created playlists do not?
I moved the library manually to internal storage, and SMusic accessed it OK. Curious thing was that SmartSwitch could not see SMusic at all on the old phone, so I instead downloaded it onto the new phone from PlayStore. I think I have found the problem on the playlist import. Some of the library on the old phone is on an sd card, which is not yet in the new phone, and some of the playlist paths doubtless refer to files on the missing sd card. It might be that import (in the new phone) tried to parse the paths, couldn't find some of them, and aborted the process (will verify tomorrow). Interesting thing is that the exported m3u files are a primitive plain text database and the data was good, but m3u files are apparently not what SMusic is using in normal operation, at least no m3u files found on internal storage. Maybe they are hidden?.
