Don't worry about it. It is a very old DOS command which enabled you to press your up and down cursor keys to see the last command you entered. If you want to get rid of it open notepad or wordpad and then File Open and find autoexec.bat which should be in C:\ When you have it look for a line which says doskey and type in front of it rem. Save it and close. Next time you start your computer it won't be there.