Recently I opened a video posted on one of my Facebook pages. A dialogue box came up saying that my computer had been infected by a trogan and to contact Microsoft to rectify the problem,. I immediately shut down my computer and waited for about 10 minutes On rebooting I scanned my computer with my installed apps Superspyware and Total Internet Security but neither of them advised me that a there was a trogan infection. However since that time my bookmarks have been taken over by FB paged who I subscribe to and don't allow me to access the original bookmarked URL Please give me guidance how I can rectify this situation