Now with a little bit of searching I've found a Windows based tool that claims it can recover a GUID partition table called Partition Guru Professional Edition (the free version does not handle > 2 TB ...
Format disks / images Fix a partition table, recover a deleted partition Recover the GUID Partition Table from its backup Locate partitions which are inaccessible / ignored by the OS Verify the ...
If while installing Windows on your computer, you receive Windows cannot be installed to this disk, The selected disk is of the GPT partition style message, maybe something here will be able to help ...