Sky + feature not working after power cut?

Hello, my sky+ box is not longer working after a power cut. I can watch sky channels, but all the Sky+ facilities have been lost, an error message comes up when i try to record a programme or pause what i am watching saying "A sky+ error occurred", i then have the option to go "back up" to continue without sky+ or press "select" to fix the fault, which doesn't work, it just switched the box off.
Help any suggestions??
We have a thomson sky box