Hello Campbell,

Would you mind letting me know if the issue occurs with my sample attached? Let me know if you have any additional questions as well.

Hello,

While Mike D is creating a sample, would you be able to supply a call stack? It's possible that the call stack might have some information that we can use.

Hi Michael,

Directly on the form is an UltraTabControl.  The UltraExpandableGroupBox controls sit directly within an UltraTabPageControl, with nothing obstructing them.  As each groupbox expands or collapses I rearrange the position of the group below so it always sits just beneath.  We have a total of 17 expandable group boxes on this tab.

And yes, the GroupBoxPanel renders fine, it's just the UltraExpandableGroupBox throwing the actual exception.

Thanks,
Campbell 

Hello Campbell,

Thank you for following up. I'm fairly close at completing a sample that I need, I just have a couple questions. Are you using a ribbon or tab control to house your expandable groupboxes? Do you have any other panels or controls that the groupboxes may be obstructed by that I may need to be aware of to properly reproduce this? It appears that the groupbox controls are throwing the exception, but not the panels that reside, which contain your controls.

Let me know if you have any additional questions.

Hi Michael,

I feared you'd ask me for a sample.  No, we haven't been able to reproduce either - it only occurs on our client's virtual setup, so I suspect it's something to do with the way they have this set up, perhaps not specifying enough resources somewhere.  That said, I can't understand why it's an issue in 15.1, but it wasn't in 13.1.

Further to this, it only affects the Office2007 theme.  If they switch to a different theme (e.g. Visual Studio 2005) then they do not get the issue.

Thanks,
Campbell