Due to work/life factors I have only just got round to upgrading from 3 - 4, but wanted to keep up to date.
A couple of issues popped up, but now at a monumental inpasse, probably due to lack of knowledge.
Current situation is that I have no webGUI but I can still ssh, but somehow looks like I have uninstalled something I shouldn't have - openmediavault - not quite sure how.
Result of apt-get -f install is:
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up openmediavault (4.1.26-1) ...
Failed to preset unit: Unit file /etc/systemd/system/openmediavault-issue.service is masked.
/usr/bin/deb-systemd-helper: error: systemctl preset failed on openmediavault-issue.service: No such file or directory
dpkg: error processing package openmediavault (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)
Any help greatly appreciated.