Yahoo messenger problem

Suddenly my yahoo messenger gives problem. Whatever I type in or messages received are not visible. I checked yahoo help, it said i should uninstall java,flash,IE etc n reinstall. I did but no use. It all started after I used some application in facebook, some video chat application. After that some scripting problem arose in IE, whenever I tried to open a site it crashed saying tab recovered something. Still not able to see msgs in yahoo. Any help?