I’ve been doing a bit of Web UI work recently and everything was going fairly smooth until yesterday when I tried opening one of my CSS files in Visual Studio and was promptly greeted with a dialog reading “The operation could not be completed. Unspecified error” and the editor never opened.  A little hunting for the error message and “CSS editor” revealed that the Web Standards Update for Microsoft Visual Studio 2010 SP1 was likely to be the culprit and uninstalling should resolve the issue.

I closed Visual Studio, uninstalled the update, and sure enough, when I reopened my project the CSS file opened just fine. I haven’t reinstalled the update yet. Maybe I’ll try again soon but it seems from the comments on the component’s page that this is a common issue.

More information:

• CSS Source Editor won’t open in Visual Studio 2010 Professional
• Web Standards Update for Microsoft Visual Studio 2010 SP1
  (be sure to check the “Reviews” and “Q and A” tabs)