Unable to clone or backup MSSQL database in Plesk: Property TextHeader is not available for StoredProcedure <...>. The text is encrypted

Symptoms

• Copying a MSSQL database in Domains > example.com > Databases > example_db > Copy fails:

  PLESK_ERROR: Unable to clone database.

  The following error is logged into the file %plesk_dir%admin\logs\php_error.log:

  CONFIG_TEXT: ERR [panel] Task failed: id=1615, pid=25416, type=db-clone, error=dbbackup failed: Unable to copy database 'example_db' to database 'example_db_clone''
  
  Script transfer failed.
  Script failed for Server '.\MSSQLSERVER2014'.
  Property TextHeader is not available for StoredProcedure '[dbo].[stored_procedure_name]'. This property may not exist for this object, or may not be retrievable due to insufficient access rights. The text is encrypted.
  
  (Error code 23)

• After the backup process, the following error is shown in Tools & Settings > Backup Manager :

  CONFIG_TEXT: Warning:domain "example.com" Unable to backup database content. Database example_db. Db server .\MSSQLSERVER2014:[Cannot open database "example_db" requested by the login. The login failed. Login failed for user 'NT AUTHORITY\SYSTEM'.]

Cause

The database contains encrypted procedures, which are not supported by Plesk.

This has been reported as bug ID PPPM-5693.

Resolution

Currently, the only solution is to avoid using encrypted procedures in the MSSQL databases.