Hi,
What version of Visual Studio are you using? What is your web project type, website or web application?
Could you please provide us with more information to see if we can repro this issue?
Please try to install the latest service pack for it or repair it. If you installed any Add-in for it, you can try to eliminate the possibility that third party Add-ins are causing problems.
Besides, the .webinfo file is used in the File System Web site project (http://msdn.microsoft.com/en-us/library/e5x4xz73.aspx), and App_Code folder is designed for web application project. Please verify these information.
If this doesn’t help you, please feel free to let me know.
I hope this helps.
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