Backups to Dropbox fail Plesk Obsidian update to 18.0.52: Unable to create the remote backup: (1): expected value

Symptoms

• After new Plesk Obsidian update to 18.0.52, there is an issue managing backups using Dropbox.

• The following message are shown while trying to save the backup on remote Dropbox:

  ERROR: () Unable to create the remote backup: <unspecified file>(1): expected value
  WARNING: () Unable to delete the incomplete remote backup. Error: Failed to exec pmm-ras: Exit code: 1: <unspecified file>(1): expected value

• It affects both Windows and Linux OSs.

Cause

Product issue:

• EXTPLESK-4582 "Error performing server backup or restore from Dropbox"
  Fixed in:

Resolution

Workaround

If update is not possible for some reason you may use local storage for backups.