The Plesk Mail Importing tool fails to import mailbox data: mail-migrator: Permission denied

Symptoms

• The Mail Importing tool fails to import mailbox data with the following error:

  Failed to connect to the source server and copy mail messages

  When clicking on "details" in the error message, the following error message is shown:

  Command execution failed on the local server with non-zero exit code. command: /usr/local/psa/admin/plib/modules/site-import/backend/lib/python/parallels/core/extras/mail-migrator/linux/mail-migrator migrate --source-account-
  ...
  exit code: 126 stdout: stderr: /bin/sh: /usr/local/psa/admin/plib/modules/site-import/backend/lib/python/parallels/core/extras/mail-migrator/linux/mail-migrator: Permission denied

Cause

The Site Import extension is corrupted.

Resolution