Two of the miners I have at home aren't working. One is running a 7950 the other a 7870. They had been working fine for months but then suddenly stopped. I restarted both machines and went to start guiminer but after clicking "start mining" nothing happens.

I'm getting the same errors on both machines which is strange. Any ideas?

Traceback (most recent call last):
  File "guiminer.py", line 857, in toggle_mining
  File "guiminer.py", line 1005, in start_mining
  File "subprocess.pyo", line 621, in __init__
  File "subprocess.pyo", line 830, in _execute_child
WindowsError: [Error 2] The system cannot find the file specified