the mount button appears but nothing is displayed when clicked
on the server side I tested the manual mount command
sudo urbackup_mount_helper mount client 170318-1631_Image_C Image_C_170318-1631.vhdz
Loading FUSE kernel module…
Starting VHD background process…
Waiting for background process to become available…
Timeout while waiting for background process. Please see logfile (/var/log/urbackup-fuse.log) for error details.
UrBackup mount process returned non-zero return code
the urbackup-fuse.log shows
2017-03-26 11:51:25: Mounting VHD via fuse…
2017-03-26 11:51:25: VHD-Parent: “/media/BACKUP/urbackup/client/170318-1631_Image_C/Image_C_170318-1631.vhdz”
2017-03-26 11:51:26: Volume offset is 524288 bytes. Configure via --offset
2017-03-26 11:55:28: Mounting VHD via fuse…
2017-03-26 11:55:28: Volume offset is 524288 bytes. Configure via --offset