Plesk migration won’t start: urlopen error [Errno 99] Cannot assign requested address

Symptoms

Plesk migration fails to start with this error:

urlopen error [Errno 99] Cannot assign requested address

Cause

This happens when the target server has a misconfigured IP address, and Plesk Migrator fails to test connections.

Resolution

Repair the broken IP address configuration and restart migration.

1. Log in to Plesk on the target server

2. Go to Tools & Settings > IP addresses and press Reread

3. Press the Repair option or remove the address from Plesk

4. Go to Tools & Settings > Migration & Transfer Manager and press Finish Migration

5. Start a new migration