Ala'a Alnajjar

Everything about ASP.Net

How to fix "Validation(): Element 'xxxx' is not supported" Visual Studio 2010

Since about a month ago,I started to get validation warnings at design time on asp.net server controls (any control actually) within the html design view for VS 2010,intellisense on all controls would not work at all,the messages look like this:

Validation(): Element 'Label' is not supported.
Validation(): Element 'GridView' is not supported
....etc

The compilation done successfully but the warnings still exist and intellisense is not working at the source tab

I tried to reset the settings of VS 2010 ,disabled all extensions and few other ideas but none of them solved the issue,I got stuck.

I did a search over the internet about this issue and found this article on Doug Kennard's blog:
http://www.gotknowhow.com/articles/fix-validation-element-not-supported-visual-studio-2010

Splendid,that article is a life savior,the idea is to remove the folder "ReflectedSchemas" from paths:

Win XP : C:\Documents and Settings\{username}\Application Data\Microsoft\VisualStudio\10.0\ReflectedSchemas

Win Vista / 7: C:\Users\{username}\AppData\Roaming \Microsoft\VisualStudio\10.0\ReflectedSchemas

Note: make sure that "Show hidden files, folders, and drives" is selected from Folder Options,also don't forget to close VS before deleting the folder.

This solution should work for VS2010 and VS2008,at VS2008 you have to delete ReflectedSchemas from folder 9.0 not 10.0.
Posted: Aug 31 2010, 02:10 PM by alaa9jo | with 11 comment(s)
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Comments

Errors said:

Thank you very much

# February 7, 2011 2:07 AM

Khalid said:

Alaa.

You are great. Your tip was really down to the point for me. Shokran, bro.

# June 11, 2011 7:28 AM

S Sebastian said:

Thanks for the valuable info.

# June 19, 2011 4:56 AM

vot said:

thanks

# July 12, 2011 5:41 AM

Howie said:

Thanks, that was annoying! You'd think that by 2011, all the kinks would be worked out of VS.

# July 29, 2011 9:39 AM

Jon said:

Thanks man, it worked for me !! It happenned when I upgraded from VS 2008 to VS 2010 !!

# October 27, 2011 1:20 AM

piyey said:

Thanks very much, it works.

Just a little correction:

[UserName] is missed

Win Vista / 7: C:\Users\[UserName]\AppData\Roaming \Microsoft\VisualStudio\10.0\ReflectedSchemas

# November 18, 2011 9:56 AM

Deepesh said:

Thanks this worked !

# November 20, 2011 4:06 PM

Thilaga said:

Really Suberp!.

It saved my time. Thought of rebooting my clinet pc by installing VS again.

Thanks a lot.

# January 30, 2012 1:52 AM

Mort said:

Thanks, that fixed my problem!

# February 5, 2012 8:09 AM

Sumbhajee said:

Thanks a lot for this quick fix.  Had it happening to my projects randomly and just ignored it, but kind of annoying to have like 600 warnings.

# April 12, 2012 12:28 PM
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