Browser error in (IE 6)?

i developed a project in that when whe开发者_JAVA技巧n i click on any button it giving some message like..

sys.webforms.pagerequestmanagerservererrorexception:An unknown error occurred while processing the request on the status code returned from the server was:12019

it is especially in IE 7. it is working fine in firefox and IE 6. I have a doubt that when a system contain IE 6 and IE 7 this problem will get i think what do you say?. can u help me and this is my site

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Give a try at this "FIX" for Sys.WebForms.PageRequestManagerServerErrorException 12019 Problem with MultipleIEs