My Android 7.0 phone got update today from Google Play Store and now it's running Sync 2.6.0 (7871)
I have 2 connected folders and now they both show "Can't open the destination folder".
The destination folders are on my phone's external SD card and I am pretty sure Sync 2.5.x didn't have this problem (I granted SD card access). The SD card is mounted correctly and I can see all synced files from a FileManager app.
1. reboot the phone
2. check System S