Issue Upgrade to 18.0.30 - exit code 255 for most plesk console commands

[Haskalah]

I initiated the upgrade from 18.0.29 => 18.0.30. Once it finished, I was no longer able to access the panel. Most of the plesk command-line fails with an 'exit code 255', including:

plesk login
plesk repair installation -y

I tried fixing the PleskSQLServer using this article: Plesk SQL server does not start: exit status 255 to no avail. I also tried using the Reconfigurator but also without success.

I'm seeing this error in the php logs:

[2020-09-19 09:02:38] PHP Warning: require(C:\Program Files (x86)\Plesk\admin\plib\vendor\composer/../react/promise/src/functions_include.php): failed to open stream: No such file or directory in C:\Program Files (x86)\Plesk\admin\plib\vendor\composer\autoload_real.php on line 70

[2020-09-19 09:02:38] PHP Fatal error: require(): Failed opening required 'C:\Program Files (x86)\Plesk\admin\plib\vendor\composer/../react/promise/src/functions_include.php' (include_path='C:\Program Files (x86)\Plesk\admin\plib\vendor/plesk/zf1/library;C:\Program Files (x86)\Plesk\admin\plib') in C:\Program Files (x86)\Plesk\admin\plib\vendor\composer\autoload_real.php on line 70

 

[Bitpalast]

There must have been an error during the upgrade. You'll need to look into your upgrade log or you can try to run the upgrade again from your console.

 

[Haskalah]

The upgrade log appears to be cut off, so perhaps something stopped it mid-upgrade? I do see the missing dependency as one of the last things that was noted as "removed" before that.

How would I rerun the upgrade? I've tried various plesk installer commands but they all note

Detecting installed product components.
Retrieving information about the installed license key...
Determining the packages that need to be installed.
You already have the latest version of product(s) and all the selected components installed. Installation will not continue.

 

[Bitpalast]

Have you tried this one, too?

# plesk installer --select-release-current --reinstall-patch --upgrade-installed-components

 

[Haskalah]

I receive

C:\Users\Administrator> plesk installer --select-release-current --reinstall-patch --upgrade-installed-components
WARNING: Command line option '--reinstall-patch' is deprecated and will be ignored.

And the same message as above, unfortunately.

 

[Bitpalast]

Oh, yes, Windows, sorry.
--> Plesk support case. Please open a ticket with them.