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Knowledge Base

Plesk interface is not accessible: Class ‘pathtoclass’ not found

 
centoscentos 7databasedebiandomains

Symptoms

  • Plesk is not accessible with one of the following error messages in a web-browser:

    Server Error 500

    Call to undefined method Plesk_Mode::isExternalOwner()
    Type Error
    Message Call to undefined method Plesk_Mode::isExternalOwner()
    File login_up.php


    ERROR: Server Error 500 DI
    NotFoundException
    No entry or class found for 'PleskGraphQlService'
    Type DI NotFoundException
    Message No entry or class found for 'PleskGraphQlService' File Container.php Line 135


    Error: Class 'PleskEmailActivationEventListener' not found


    ERROR: Class 'ComposerAutoloadClassLoader' not found (autoload_real.php:23)


    ERROR: Zend_Exception: File "Zend/Db/Statement/Pdo.php" does not exist or class "Zend_Db_Statement_Pdo" was not found in the file


    ERROR: require_once(): Failed opening required 'vendor/autoload.php' (include_path='/usr/local/sb/include:/opt/psa/admin/plib:/opt/psa/admin/externals') (init.php:4)


    Warning: Unknown: failed to open stream: No such file or directory in Unknown on line 0
    Fatal error: Unknown: Failed opening required 'auth.php' (include_path='.:') in Unknown on line 0


    PHP Fatal error: During class fetch: Uncaught ParseError: Unclosed '(' in /usr/local/psa/admin/plib/Os/UtilTrait.php:104

  • When accessing the Domains page, the following error message is shown in Plesk:

    Call to undefined method PleskSessionContext::getUser

  • When creating a new subscription in Plesk at Subscriptions > Add Subscription or a new database at Domains > example.com > Databases > Add Database, the operation fails with:

    Zend_Form::isValid expects an array

Cause

The plesk-core package is corrupted.

Resolution

  1. Connect to the Plesk server via SSH.

  2. Download the plesk-core package from http://autoinstall.plesk.com/pool/ using the wget utility.

    Note: Make sure to download the plesk-core package equivalent to your Plesk version PSA_18.0.xx_xxx and OS dist-rpm-[OS_VERSION]. Run the command plesk version to find the Plesk version and OS.

    In this example, we're downloading the plesk-core package for Plesk Obsidian 18.0.37 PSA_18.0.37_6686 on CentOS 7 dist-rpm-CentOS-7-x86_64. The full path to the plesk-core package will be:

    # wget http://autoinstall.plesk.com/pool/PSA_18.0.37_6686/dist-rpm-CentOS-7-x86_64/base/plesk-core-18.0-2.centos.7+p18.0.37.2+t210809.1806.x86_64.rpm

  3. Install the plesk-core package downloaded on step 2:

    • on CentOS/RHEL-based distributions

      # rpm -Uvh --force --nodeps plesk-core-18.0-2.centos.7+p18.0.37.2+t210809.1806.x86_64.rpm

    • on Debian/Ubuntu-based distributions

      # dpkg -i plesk-core-18.0-2.centos.7+p18.0.37.2+t210809.1806.x86_64.rpm

  4. Run Plesk Update:

    # plesk installer update

  5. Restart the Plesk services:

    # service sw-engine restart && service sw-cp-server restart

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