Backup Error code: 0x81000019

Have you made any changes in your partitioning structure at all? Post back screenshot of Disk Management - Post a Screen Capture Image

Are there any other performance issues? Go over your install thoroughly with the Troubleshooting Steps for Windows 7 which will turn up most problems.

If its limited to Win7 backup then I'd consider an alternative like Macrium - Image your system which is heavily preferred here, or the premium Acronis app which comes with any WD or Seagate drive in the mix. These are better choices anyway.

Is this exactly what you did? System Restore.

WD Data Lifeguard doesn't have a bootable app any longer except on some boot disks that are not supported here. It should be definitive.

Make sure your data is backed up from External and then also run a full Disk Check with both boxes ticked.

Thanks for the heads-up Michael. The bootable Data Lifeguard disappeared several years ago. I inquired of WD a year or more ago and heard nothing. John Carrona who keeps HD Diagnostic list told me in November it still wasn't available for some reason. All that remained on their website in that time was making a bootable floppy.

That .pdf tutorial on making flash stick with Rufus apparently just came out in Feb 2014 after several years' wait. I don't know if its been changed on all of their Product pages but will bookmark it.