Symptoms
Cannot start Plesk migration:
urlopen error [Errno 99] Cannot assign requested address
Cause
Plesk Migrator tries to check connection to the target host. It takes the first IP from
table and tries to establish connection. The first IP is misconfigured or does not exist on the target server.
IP_Addresses
Resolution
1. Log in to target Plesk server
2. Go to Tools & Settings > IP addresses and click Reread. Repair link should appear next to the problematic IP address. Click Repair or remove the address from Plesk.
3. Finish current migration with Tools & Settings >  Migration & Transfer Manager > Finish Migration and start over.
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