Unable to access Plesk GUI after upgrade from Onyx to Obsidian: HTTP 500.19 – Internal Server Error

Symptoms

• Unable to access Plesk GUI after upgrade from Onyx to Obsidian, one of the following error is shown when trying to access Plesk URL https://localhost:8443 from the same server:

  HTTP Error 500.19 - external Server Error
  The requested page cannot be accessed because the related configuration data for the page is invalid.
  Detailed Error Information:
  Module IIS Web Core
  Notification BeginRequest
  Handler Not yet determined
  Error Code 0x80070005
  Config Error Cannot read configuration file due to insufficient permissions
  Config File ?C:Program Files (x86)Pleskadminapplicationsmbpublicweb.config
  Requested URL https://localhost:8443/smb/web/view
  Physical Path C:Program Files (x86)Pleskadminapplicationsmbpublicwebview
  Logon Method Not yet determined
  Logon User Not yet determine

  HTTP Error 500.0 - Internal Server Error
  The FastCGI process has failed frequently recently. Try the request again in a while.
  Detailed Error Information:
  Module FastCgiModule
  Notification ExecuteRequestHandler
  Handler PleskEngine-FastCGI-php
  Error Code 0x80004005
  Requested URL https://localhost:8443/application.php/smb/web/view
  Physical Path C:Program Files (x86)Pleskadminhtdocsapplication.phpsmbwebview

  The following error appears when running Plesk Reconfigurator:

  Unable to execute "C:Program Files (x86)Pleskadminbinwebsrvmng.exe" --configure-plesk-website:
  The parameter is incorrect. (Error code 87) at Unable to add the member (IIS AppPoolPleskControlPanel) to the group (psaadm_users)
  at (UserManagement::LocalGroup::addMember line 77)
  at addMember(psaadm_users, IIS AppPoolPleskControlPanel)(UserManagement::LocalGroup::addMember line 80)
  at _configurePleskSiteAppPool()(PleskWebSite::_configurePleskSiteAppPool line 58)
  at configurePleskSite()(PleskWebSite::configurePleskSite line 414)
  at execute console command --configure-plesk-website(vconsoleapp::start line 93)
  at execute "C:Program Files (x86)Pleskadminbin64websrvmng.exe" --configure-plesk-website(vconsoleapp::run line 110)

• Unable to access Plesk:

  ERROR: Exception: Unable to get PSADb administrator password: Access is denied. (Error code 5) at Unable to connect to pipe .pipeP_d6998bb5-b5c2-49f5-a7c6-c44831661eb2<br> at (Con::ClientOverlappedPipe::create line 514)<br> at Unable to call getInstance()(PleskSrvClient::getInstance line 364)<br> at (zif_get_psadb_admin_password line 250)

• Running lusrmgr.msc utility shows that the Plesk server is a Domain Controller:

  The computer HOSTNAME is a domain controller.

Cause

Installing a Domain Controller on the same Plesk server is not supported (Scenario 2)

Resolution

The following options are available:

• Restore the Plesk server from a previous snapshot / full server backup and migrate to a new Windows server.

• Restore the Plesk server installation on a new Windows server

In case a Domain Controller is required, attach the Plesk server to an external Domain controller (Scenario 1).