Drive ejecting during Time Machine or other Backup Retrieval

SOLUTION FOUND--- FINALLY
I tried every which way but loose to do a full backup restore after my MacHD failed. They installed a new HD and told me to just boot up and restore.
Ha! No chance. I had both Time Machine backup and also a WD smartware back up and every single time, right before the end, I would get the "disk improperly ejected" message....!
I finally called Apple and asked if they still had my "semi-failed" drive so I could retrieve files manually by casing the old external drive.
The tech that I talked to was a true "genius."
I told him all the tedious steps I went through for two straight days and he asked:
When you connected the External Drive -- did you connect it to the same USB port?
Oh....wow....... ! I didn't know! I use all the ports since I keep three backups --the WD smartware, Time Machine, and a partial/daily drag n' drop for JOBS.
So --- I started over disconnecting all other drives and one at a time, I plug in the USB cable of the SOURCE backup external to each USB port, run back up, and fail, change port, fail, and finally .... VOILA!!!! I found the "magic button."
My backup went through and I am a happy camper.
Finally I can sleep.
