Iomega Prestige 2TB not detected by ReadyNAS NV+

That is good. Be advised, however, that if you have the opportunity to reformat it to FAT32 or EXT3 in the future, it will perform the backup faster. The routine for CIFS to NTFS is not as efficient as to the other two file formats. Of course the big advantage of either NTSF or FAT32 is that is can be directly read by Windows. Of course as you have now discovered, moving terrabytes of information across USB will take a long while. Not something you want to do on a frequent basis.

With that much data, you might want to see about a second NAS. I was running a single NV+ for three years, working up to about 600GB of data. I upgraded by adding a new NVX (now discontinued in favor of the Ultra 4) and at the suggestion of a few other members of the forum, used my NV+ as a backup target. Backups that used to take hours (I would only update the backup of media, it was 400+ GB so took forever to back up) became minutes. Once you have your initial backup done NAS to NAS, using File Transfer Protocol (FTP) you switch the method from FTP to rsync and it only takes minutes to synchronize the files share by share on the two machines. In addition, if something happens to one machine (fan, drive, PSU, whatever) you can still run off the backup. Although expensive, NAS to NAS is the only way to go when you measure your data in terrabytes. (My volume is now up to 1.7TB. Video sure eats up the drive space.)