I have en external HD that I use with OS X. When I bought it, it was formatted for Windows (NTFS). I deleted the NTFS partition and created a new HFS+ partition. Then I copied 500 GB of material over.
Everything works fine when the external HD is directly connected to a Mac, but if I want to share the external HD by connecting it to a Time Capsule, I get an incorrect error message about the HD needing repair.
The problem is that the partition MAP is still in Windows format. For Time Capsule to recognize the disk, the partition map has to be in Guid Partition Table (GPT) format.
To do this, I have to delete the existing partition map. Will this also delete the underlying partition contents?