Unrecognized tag prefix or device filter 'asp' in VS2012

Question

I recently installed VS2012 and working on work projects that I used to work on with VS2010. I never had an issue with VS2010 not recognizing asp prefixed tags but VS2012 is. I tried deleting the ReflectedSchemas folder under

C:\Users[User_name]\AppData\Roaming\Microsoft\VisualStudio\11.0\

but still not working. Anyone ran into this issue in VS2012?

Answer 1

Closing and reopening the file (.aspx file not solution) from solution explorer worked for me in visual studio 2015. Before trying anything else you can give it a try.

Answer 2

Do you happen to have something like this in your Web.Config:

<pages>   <controls>     <add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />     <add tagPrefix="asp" namespace="System.Web.UI.WebControls" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />   </controls> </pages> 

In that case, remove the entries for the asp tagPrefix (remove the entire section if no other tagPrefixes are left). This worked for me.