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
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.
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