hiim using cad 2010 for long time,but today wen i try to open my cad this message come up "a software problem has caused autocad to close unexpectedly" is there anybody to tell me what is this error and how can i solve it????pleas help me thanks

That's the extent of the message?First, I would shut my computer down completely, wait 20 seconds, boot back up again and try restarting AutoCAD.  It could have been a momentary glitch.If that doesn't work and you get the same message then you could try to REPAIR AutoCAD via Windows Add/Remove Programs.Do not uninstall/reinstall AutoCAD until you have tried the REPAIR option.If you have to uninstall/reinstall AutoDesk has a recommended procedure for users to follow posted at their website.