If your trying to run SCANDISC and it keeps restarting even after you closed all items shown in your systam try.
there could be at most two other items not shown which are interrupting the process.
1) If you have a scanner - goto its controls or control panel specifically for the scanner.
Make sure to completely trun it off from the PC communication.
Its communicating with the PC repeatedly incase your PC needs to tell you
(THIS ITEM not communication with port # "__" )
just make the PC belive that the scanner is removed
2) If you have a battery back-up like an APC - UPS unit
youll need to turn that off as well-
dont turn off the power of the unit
just turn off the monitoring.
Although this wont SOLVE all problems - it is something that COULD be for you.