Windows home server 2011
On my Server, a RAID 5 controller manage 4 one TB HDisks Therefore the OS "sees" one basic disk of 3 TBytes. But 750GBytes remain "Unallocated" and connot be used by Windows home server
Has anybody an idea how to free this unallocated part in order to use it?
If the volume on your RAID array was formatted using an MBR partition table, any space above 2 TB is inaccessible. You can convert an MBR disk to a GPT disk, if the disk is empty (no partitions); see e.g. this TechNet article for more details: