My Passport Ultra 2TB Metal Edition

Hello.
Thank You for the oppourtunity to ask a technical issue here. I have a 10g computer, the computer says that I have on the hard drive 264.43 GB free of 931.48 GB. I purchased a 2TB to down load my computers information onto. When I installed the Passport Ultra, and proceeded to back up onto the drive, it started and then after a few minutes said that it was unable to complete the back up because there wasnt enough space. on the passport drive.
I have a cannon zoom browser photo program installed in my computer, and have a few years of pictures stored there, that is what my objective is to download onto the passport. I’am starting to think that maybe my problem is there with the amount of pictures that are there. But that I look at my computers drive and it says that there is still free space, so I’am confussed.
Any suggestion or feed back would be appreciated, Thank You.

Hello,

What software are you trying to use to backup the data?