Issue problems after ubuntu update to 16

[TauTaude]

I did a distupgrade according to How to perform dist-upgrade procedure on Linux server with Plesk?
afterwards a lot was broken, including plesk. I fixed plesk with this
# plesk installer --select-release-current --reinstall-patch --upgrade-installed-components
# plesk repair installation
# plesk repair all -y

The last command gave me this error for a lot of sites

File not found: oeschey.de.conf
  File not found: promise-guild.de.conf
  File not found: perforations.de.conf
  File not found: raahoorkhuit.de.conf
  File not found: blog.oeschey.de.conf
  File not found: concertshots.de.conf
  File not found: larsoeschey.de.conf
  File not found: machdasmalvegan.de.conf ........................... [ERROR]
    Repairing server-wide configuration parameters for web servers .. [OK]
    Updating the file of sharing passwords and permissions of users
    according to actual information ................................. [OK]
    Repairing web server configuration for all domains. This aspect
    can be used with individual domains ("plesk repair web
    example.com"), and on the server level ("plesk repair web") ..... [2020-11-11 23:55:41.316] ERR [util_exec] proc_close() failed ['/opt/psa/admin/bin/httpdmng' '--reconfigure-all'] with exit code [1]
Error occured while sending feedback. HTTP code returned: 429
[FAILED]
    - httpdmng failed: Execution failed.
      Command: httpdmng
      Arguments: Array
      (
          [0] => --reconfigure-domains
          [1] =>
      blog.oeschey.de,concertshots.de,larsoeschey.de,machdasmalvegan.de,oeschey.de,perforations.de,promise-guild.de,raahoorkhuit.de
      )

      Details: [2020-11-11 23:55:36.671] ERR [util_exec] proc_close()
      failed ['/opt/psa/admin/bin/apache-config' '-t'] with exit code
      [1]
      [2020-11-11 23:55:37.730] ERR [panel] Apache config
      (16051353350.44983700) generation failed: Template_Exception:
      AH00526: Syntax error on line 102 of
      /etc/apache2/plesk.conf.d/vhosts/blog.oeschey.de.conf:
      Invalid command 'DirectoryIndex', perhaps misspelled or defined
      by a module not included in the server configuration

      file:
      /opt/psa/admin/plib/Template/Writer/Webserver/Abstract.php
      line: 75
      code: 0
      AH00526: Syntax error on line 102 of
      /etc/apache2/plesk.conf.d/vhosts/blog.oeschey.de.conf:
      Invalid command 'DirectoryIndex', perhaps misspelled or defined
      by a module not included in the server configuration

so, thinking "DirectoryIndex" is deprecated or something, I removed it from the mentioned files.
However, i still get the same error from the repair command, even if the DirectoryIndex command isn't there anymore (plesk has it in some other file?)
Also my sites don't work, I get 403 errors, obviously that directory index wasn't deprecated, but is needed
"[Thu Nov 12 00:00:57.758955 2020] [autoindex:error] [pid 11078] [client 84.131.152.135:63737] AH01276: Cannot serve directory /var/www/vhosts/oeschey.de/httpdocs/nxc/: No matching DirectoryIndex (none) found, and server-generated directory index forbidden by Options directive"

Any ideas how to fix that mess?

 

[Bitpalast]

Have you checkmarked "mod_dir" in "Tools & Settings" > "General Settings" > "Apache Web Server"?
Oh sorry, that is not available in many settings, so probably you cannot see it there either.

 

[TauTaude]

actually that was a great hint... I had no mod_dir there, but a "dir" setting (probably the mod_ prefix is omitted with all modules). I activated it, and was able to fix the configs from the plesk GUI