Visual Designer errors, when there are no errors

I get errors when viewing forms and there are not any. I can close VS and reopen and it is fine. What cases this? Can it be fixed without closing?

From stackoverflow nportelli

• what's on your form? Is it only .Net controls or some 3rd party/custom user control?

  Try it in debug mode step by step if you just have no hope left...

  From Miles

• It has custom user controls. Within the solution.

  From nportelli

• Verify none of your custom user controls has any code errors.

  Also try starting up Visual Studios using devenv /resetskippkgs from the command prompt. It will reset packages if there is an error in loading.

  From David Basarab