if you modify sql connect string in web.config, and the page of asp.net config to happen below event, you must compile your project after open that page again.
yJvx[r^?O0>V1CfRJpFVlc]Tk6H}=g~0_aZZ#cmH
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error messeng
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yJvx[r^?O0>V1CfRJpFVlc]Tk6H}=g~0_aZZ#cmH
There is a problem with your selected data store. This can be caused by an invalid server name or credentials, or by insufficient permission. It can also be caused by the role manager feature not being enabled. Click the button below to be redirected to a page where you can choose a new data store.
yJvx[r^?O0>V1CfRJpFVlc]Tk6H}=g~0_aZZ#cmH
The following message may help in diagnosing the problem: Could not load type 'xxx.MvcApplication'.