Unrecognized tag prefix of device filter 'asp'

Posted on 2013-05-28
Last Modified: 2013-05-29
Why do these warnings appear? Unrecognized tag prefix of device filter 'asp'

<asp:GridView id="grdWatchList" runat="server"  

            Width="600px" Caption="Best Picks List "  
            BorderColor="Black" BorderStyle="Double" BorderWidth="1px"
            BackColor="Azure" AlternatingRowStyle-BackColor="#FFFF66"
            AlternatingRowStyle-BorderStyle="Solid" Font-Names="Arial"
            Font-Size="10pt" AutoGenerateColumns="False"
            DataKeyNames="SymbolID" PageSize="3"
            CaptionAlign="Left" ForeColor="Black"
            <Columns> Validation(HTML5): element 'columns' is not supported.

Is documentation available?

Question by:Dovberman
  • 3
LVL 35

Accepted Solution

Miguel Oz earned 300 total points
Comment Utility
Check your web.config as per suggestions below:
What kind of project is it? New? web app or site?

Author Comment

Comment Utility
This is a new web site project.

Author Comment

Comment Utility
Updating the Controls section of web.config to 4.0 resolved the issue.


Author Closing Comment

Comment Utility
Thank you.

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