I’m currently running Insync on my desktop running Linux Mint 20.2. Because of problems with Chrome Remote Desktop [CRD], I currently have two users running simultaneously. One user [remote] is running CRD, Insync, and any other applications I want to start on boot. The other user [local] is what I use when working at the desktop. All of my Insync files are owned by remote, and everything is stored in a luks container mounted directly under /media [/media/directory], not under either of the user names. However, I was working on something new today and created the file with local. Both users are members of each other’s groups, and they have no problem reading or writing files in each others directories. The problem is that the file created by local can’t be uploaded by Insync. The error says that I have to allow read and write permissions, but both users already have those permissions.
Hey @farside268! My apologies for the trouble. Could you please send your logs.db and out.txt files to support@insynchq.com? Please do include a link to this post for my reference 
Those two files can be found in ~/.config/Insync.
That may be a problem. I’m a lawyer, so I have to be careful with log files including any confidential information. The out.txt file is currently 26 MB and the logs.db file is 36 MB, and I can’t search through them thoroughly enough to find everything to redact it. Also, I think I’ve mostly resolved the problem by updating my umask so all created files have group access. I’ll look around and follow up.