I have suddenly started getting this error in visual studio when viewing two certain controls in the development designer mode.

It is no an array I have programmed but rather the error pops up when I try and view my webuser control in design view. The project all compiles and runs without a single warning or error, the codebehind page operates fine.

The only problem that I can no longer view the problem page in design view and if I view the markup I have lost intellisense and the asp controls from the toolbox.

Anyone else suffered this and fixed?