We try to migrate from Plesk 7.5.6 version to Plesk 11.5 and it shows the following error:
Error: Migration from Plesk version 7.5.6 is not supported.
We tried to update the source server, but Plesk shows that there are no updates available.
Migration is supported for Plesk versions 8.6.1 and higher. Please, check release notes for Plesk 11.5
You should update source server to the 8.6 version, at least. For versions prior to 10.x it is not possible to upgrade via autoinstaller utility. Please download and run the following packages to upgrade Plesk Panel: