Migrating in plesk shows an error. Checking the IP address pool in plesk show this

2607:5200:1800:1000:226:18ff:fe24:4e35  (dedicated)

Trying to remove it produces an error:

Error:   Cannot remove the IP address 2607:5200:1800:1000:226:18ff:fe24:4e35  because it is the last IP address present on a network interface.   

Disable IPV6 – http://wiki.centos.org/FAQ/CentOS6#head-d47139912868bcb9d754441ecb6a8a10d41781df

Restart plesk and re-read the IP address pool in plesk > Tools and Settings > IP Addresses > Re-read IP’s