i have windows security but it will not run. it was running fine until the other day when it just stopped all together. windows defender wont even run anymore. on start up keep getting error messages. can i uninstall windows security and reinstall it? can you help? my computer is running slow and i cant figure out why. i have laptop. also how can i upgrade from windows vista to windows 7?

Please post your query in Windows 7 forums as this forum is dedicated used for windows server technology. http://social.technet.microsoft.com/Forums/en/category/w7itpro/

It seems that it is a Windows Vista system so here is the Windows Vista forum: http://social.technet.microsoft.com/Forums/en-US/category/windowsvistaitpro/ Please remember provide the error message you got on startup. "Windows Security" is not an exact program, so you should point out the exact thing which is stopped working (if not only Windows Defender), which including Windows Firewall and maybe Windows Update.Shaon Shan |TechNet Subscriber Support in forum |If you have any feedback on our support, please contact tngfb@microsoft.com