one possible solution to error: [UserControl] is not a known element

[denny1824]

After adding a user control I was getting the error that the user control is not a known element.

Tag is:

 <%@ Register TagPrefix="uc" TagName="uc_name" Src="~/folder/filename.ascx"  %> 

Added in code as:

 <uc:uc_name ID="userControl1" runat="server" /> 

The user control shows on the page as expected, but the IDE intellesence marks the TagName in the code as being not a known element.

While searching for an answer, I found a lot people with this same problem but no solutions.

My solution was to clear the intellesence cache. I have windows XP. I went to:
c:\Document and Settings\[myUserName]\Application Data\Microsoft\VisualStudio\8.0\ReflectedSchemas. I hit Crtl-A and then Delete.

As always, delete files at your own risk. I hope this helps.