Thanks to everyone who contributed information on expanding the storage capacity of the DirecTV. It was really helpful in installing expanded capacity on my new HR44NC-500. I chose a Western Digital WD Green 4 TB Intellipower WD40EZRX. The model number is WDBH2D0040HNC-NRSN. I mounted it in a Vantec NexStar CX enclosure. It has both USB 2.0 and eSATA. I tried shutting down the HR44, plugging in the drive, powering it up, and then powering up the HR44 again. It wasn't recognized. So I attached the drive to my desktop and formatted it to make sure it worked. It did and reported about 4tb of space. I then reattached the drive to the HR44 and powered it up and it worked! Don't know if it was formatting it that made the difference, but it works, and that's all that I care about. Thanks for all the help.