system

While it is scanning you computer don't use it till it's done because that's why it's running slow go fine a few things to do while it's scanning to kill time watch Tv. or wash the dishes.

it is not something it should do, definitely... have you installed new software or changed any new hardware? if so, those may be the reasons. have you changed any of the settings of your pc? if so try to go back to the last known safe configuration. which sites have you visited recently? have you opened any "strange" email? maybe you got infected but nor your antivirus nor your spyware detector find the menace. if not...i don't know what to think. try scanning your system online, there some sites where you can do it for free (try in the kaspersky site, for instance). ultima ratio...backup your data and format your hard drive. but it really expensive, in terms of time and bore. let me know if you can solve the problem, bye!