Repeating error in panel.log: Unable to get key: Repository is not opened

Symptoms

The following error repeats multiple times in /var/log/panel.log whenever the server's license information is updated (for example, during the Daily Maintenance Task):

ERR [panel] Unable to get key: Repository is not opened

Cause

Corrupted /etc/sw/keys/registry.xml file.

Resolution

Regenerate the corrupted file:

1. Connect to the server via SSH

2. Remove the file:

   # rm -f /etc/sw/keys/registry.xml

3. Regenerate it with Plesk repair tool:

   # plesk repair fs -y