My yahoo is messing up can someone help?

Ok I put Service pack 2 on here I have Xp pro and yahoo worked fine up until last night it came up and said when I tried to open it Yahoo has encountered a problem and needs to shut down so I reinstall it and it does the same thing so I uninstalled service pack 2 rebooted and installed yahoo once again and it worked until I rebooted my computer and it stopped working again and said once again yahoo has encountered a problem and needs to shut down and I reinstalled it again and it works but for how long im not sure is there anything I can do to fix this? it would help me out a lot if someone could help me Itd be greatly appreciated.. Thanks..