Hello, I have a 500GB WD Passport, 200GB partitioned for all my movies, etc, and 300GB partitioned for TM. I wanted to get rid of the TM partition. However, when I try to delete the partition, the minus arrow is greyed out, and on the side, it says 'this partition cannot be modified'. The only way to get rid of it is to delete my whole external HD, both partitions. However, I want to keep everything in partition 1. Any ideas? I've tried going to the TM partition and clicking erase.