There are a few reasons why an Xbox 360 may not be detecting an external hard drive as a storage device. The most common reason is that the hard drive is not attachedto thebrand new Xbox 360. If you have not had any troubleviewing your data recently (you have not turned off and on the hard drive), then the hard drive may be too new and still offer no issues.
Another reason may be because the hard drive is being considered an "external" hard drive by the Xbox 360 and is not actually stored onto the brand new Xbox 360. If your Xbox 360 is not detecting the external hard drive as a storage device, pleaseistar to try this:
-ignment the hard drive to a different platform
-add an external storage device such as anSD card
-try an other method such as calling our customer service