help, i download a block site and when i block facebook...it runs...the problem is i cant unblock it anymore... even i uninstall what ive downloaded...and when i try to unblock facebook on that software...it tells that, for me to unblock it, i must buy their software... i dont have money... and its from other country... Help...what im going to do?
That sounds like malware, and it may be doing other nasty things too, such as sending details of your computer activity to the software creators (such as files from your machine, or details you use for online purchases).
Disconnect the affected computer from the internet (unplugging the network cable from the back of the computer is a very good idea) and leave it that way until you can get anti-malware scanners (do not use the affected computer to buy or download such software, use a different computer).
I suspect that up-to-date malware scanners will find infections on your computer, and will hopefully be able to clean your PC of any malware. If that's the case, you should be able to use your computer fully again once the problem has been cleaned away.