LinMad5702 0 Newbie Poster

I recently purchased a second hand IBM Think Pad. When loading my DSL onto this computer something went haywire...I am now getting a stop message Inaccessible Boot Device. It is telling me to check for viruses, remove any newly installed hard drive controllers and to check to see if my hard drive is configured properly. The problem is even after I restart the computer this is the only screen I can access, so I cannot run virus protection or any other task. Can anyone help?!?