Visual Studio 2010: Editor Slow -> SmartTags Exceptions?

sometimes the VS2010 Editor is incredibly slow (1 char/sec). But at first the same editor window, same document, performs well.

Editor: Html with Razor

I attached another VS instance to slow instance and got this multiple times in the Debug Output window:

A first chance exception of type 'System.Null开发者_Go百科ReferenceException' occurred in Microsoft.VisualStudio.CSharp.SmartTags.dll

How can I solve this?

Edit:

Additional information: if I close the tab and reopen the document it performs well but only for some time.

I had the same problem. I manage to solve this by following the steps in this blog.

I didn't have to do all of the steps. The step that "saved" me was

Disable "Rich client visual experience" in the "Options - Environment". Here's how that settings page should look:screenshot

I hope this will solve your problem.