Xigncode error 0x019101A

I've been playing CF smoothly for the past several months and just experienced this yesterday multiple times. I eventually gave up and had a go today. It was going well for awhile and it just now happened again. I should note I took in my laptop to a shop to get my hard drive fixed and they may have installed something that's interfering with the game. I've already uninstalled the free antivirus they put on. Not sure what else it could be. Everything else looks to be as I had it before the work was done. Anyone have a clue as to what's going on?