Master page - Only one instance of a ScriptManager can be added to the page
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I am using ajax toolkit in my project. My project is having a master page and i am inheriting this master page in my web pages.I am using Script manager on every page but now requirement came to display a real time clock also on the master page.I had written the code using Timer to display real time clock on master page but i am getting error "Only one instance of a ScriptManager can be added to the page. ".
 
How to fix this problem as i don't want to remove script manager from the webpages.