Smart Self Test failure/Back System Failure

Inspiron Lap top- purchased 12/2012.

following a Windows update, my internet gave problems. Message-Windows Wireless Service not running on this computer AND the Wireless Adapter not found.

A Launching Program started running upon power up. I do not know where that came from. However, it helped allowing my wireless internet to open.

NOW, I ran a Dell support scan. All tests passed with the exception of the Smart Self Test. The final message was that the Disk failure was imminent.

It suggested I back up the disk and purchase a new one.

I tried to back up the disk. At about 58 or 59%, it stopped with a message saying that the back up was unsuccessful!

What do you suggest? I cannot understand why the drive failed or why it will not back up. ERROR CODE: 0x8078012D. Please assist.