Windows 7: Problem Backing Up with Macrium Reflect

I have made many back ups using Macrium Reflect in the past. I tried to make a back up today ecountering a problem that makes my efforts fruitless. When the back up reaches 11% complete the process freezes until a notice is displayed which says "Back up aborted, error code 1117. The request could not be completed because of an I/O error.
Since I/O indicates input/output, I feared the worst and made a chkdsk on both the drve being copied and the destination drive (my external) both show no problems. Any ideas guys and gals?

Is this any help Rich ? Macrium Support Forum - Image error 1117

TY Kat,
As soon as I posted, I realized that I should take the suggestions that I have given so many. I took the Seagate Hard Drive test. It showed problems. I think that the solution to my situation is to start looking for a new hard drive.
SeaTools for Windows | Seagate
If I did not take the hard drive test the long Scan, as you suggested, would have revealed problems, as well. For your efforts and a helpful answer rep for you.