I am having the exact same problem right now and that command didn't help. I am also getting many 500 - Internal Server errors, including when I'm trying to search for new packages(not that it's necessary to update right now, I updated my system 2 days ago). I would tell you which version I have, but under the system Information page there's now only "No data to display.".
Edit: Apparently it's turned into a brick. I can't even turn SMB on, I get those 500 errors.
Edit 2: After refreshing the page, the "Enabled" switch in SMB/CIFS -> Settings is enabled, but SMB is still not working and I was not prompted with that yellow "Apply configuration changes?" Banner.
Final Edit: If anyone googles this issue and comes across this post, I was getting those dashboard issues mentioned above, along with 500 - Internal Server errors Everywhere after updating(
500 - Internal Server Error File '/var/lib/openmediavault/dirtymodules.json' contains invalid JSON: No error
). The solution that worked for me was " echo "[]" > /var/lib/openmediavault/dirtymodules.json " which i saw in a 2016 post about this json file(can't save settings without error --> dirtymodules.json).
Note: I didn't mess with any configuration files, it looks like the latest update did all this.