When I try to sync files from remote read only ftp to folder on PC where Freefilesync is installed
the error "permission denied" appears because freefilesync tried to write .ffs_tmp back to read only FTP
On earlier versions (may be 12..) FreeFileSync does not use this write-back rule....
As to my mind the quick solution for this mistake is add to set option for Source aka "Read only FTP/SFTP/etc."as on screenshot. Because in other case after download all files from Source synchronization can not end due to upper loop error.
FFS reports the problem when trying to write (a version of) the sync.ffs_db file to your FTP location.
This means you have now checkmarked the "Use database to detect changes" option in your Synchronization Settings (F8).
Using the database option requires write access to both your left and right base location.
If you again remove the checkmark for the "Use database to detect changes" option, things should work as before.
