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
ID: 39203094
Check your web.config as per suggestions below:
What kind of project is it? New? web app or site?

Author Comment

ID: 39204011
This is a new web site project.

Author Comment

ID: 39204026
Updating the Controls section of web.config to 4.0 resolved the issue.


Author Closing Comment

ID: 39204028
Thank you.

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A theme is a collection of property settings that allow you to define the look of pages and controls, and then apply the look consistently across pages in an application. Themes can be made up of a set of elements: skins, style sheets, images, and o…
Real-time is more about the business, not the technology. In day-to-day life, to make real-time decisions like buying or investing, business needs the latest information(e.g. Gold Rate/Stock Rate). Unlike traditional days, you need not wait for a fe…
This is Part 3 in a 3-part series on Experts Exchange to discuss error handling in VBA code written for Excel. Part 1 of this series discussed basic error handling code using VBA.…
Need to grow your business through quality cloud solutions? With everything required to build a cloud platform and solution, you may feel like the distance between you and the cloud is quite long. Help is here. Spend some time learning about the Con…

932 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

13 Experts available now in Live!

Get 1:1 Help Now