The solution suggested by Tonic2012 worked for us too. The issue was that for our case we had 11.1.20111.2042 installed but when I opened the csproj file in notepad it had 11.1.20111.2030. I used the version utility to fix it and it worked. Thanks.

I had the same problem after installing the 2008 Vol 3 CLR2.0 Hotfix 2039 on my machine.  The symptom was that you are no longer able to add any new Infragistics controls to forms if those controls have already been used in that project.  The control only appears in the component tray when you drop it on a form.  Previously added controls (before installing the hotfix) still appear on the form, but also appear in the component tray, and are unable to be selected for moving/resizing/etc.

I was able to fix the problem by running the Infragistics Project Upgrade Utility on all projects which use Infragistics controls.  This has the effect of making the necessary changes to the license file (which can be found under the "/My Project" folder of the project each winforms project) and also updates the project references for those controls (all of which you may have noticed reference the GAC versions of the older [pre-update] controls).

That worked.  Thanks! 

It looks like all of your designer assemblies are messed up somehow. I would try uninstalling and re-installing. If that doesn't help, you should contact Infragistics Developer Support and see if they can help you clear it up.

I can select an ultraTabControl, but I can't seem ot use any of the other controls in layout view.  It displays them on the form, but when I try to click on them, it selects the form.  If I add a new control, it doesn't even display them on the form.  It only gives the the icon on the bottom toolbar.