I have tried installing the WPF 2250 Service Release but error still persists

The fix was part of that 10.3 build so it should be addressed if it were the same issue. Is it possible that your app is using a local copy of the older version? Have you verified in the Debug->Windows->Modules that bld 2250 is loaded when the problem occurs? If you still have an issue then we'll likely need a project that demonstrates the issue. Also a complete callstack of the exception could be helpful.

I am receiving a similar error "Item has already been added. Key in dictionary: 'Infragistics.Windows.Automation.Peers.DataPresenter.LabelAutomationPeer'  Key being added: 'Infragistics.Windows.Automation.Peers.DataPresenter.LabelAutomationPeer'" during automation.  We have several different grids throughout our product and it doesn't seem to happen on all grids only some of them.

Andrew - We are currently using version 9.1 of the XamDataGrid.  Are you saying that we have to upgrade to the latest release in order for this bug to go away? 

The workaround that Andrew suggested should work as long as it is done for a ancestor of the XamDataGrid.  One scenario that I can think of where this may fail is if you are to use the workaround on the Window and within that Window use a XamDockManager with the XamDataGrid in a ContentPane.  If the pane containing the XamDataGrid were to be floated then the XamDataGrid would no longer be a descendant of the Window so the workaround wouldn't have any affect.  If this is the case, you would need to move the workaround to a container around the grid within the ContentPane such as a UserControl.

OK, settings at the solution level overridden confguration settings at project level. I'm doing the whole recompilation with solution level release settings. will update you for any issues after that.thanks

Andrew, I debugged the code and verified that these assert statements are poping up now and then.

for example Debug.Assert(adjustedScrollPosOfTargetRecord >= 0); is rasing while editing the records. I indeed built the binaries in release mode but the binaries are not dropping at bin/Release instead they always drop in bin/Debug mode. I'm not sure if some other settings are overriding. Can you help us to build the binaries in release mode and if I'm missing something?

Thanks.

I have never seen that assert being raised so I cannot say what is happening. If you want us to look into that you would need to supply a sample that reproduces the issue. Basically the only assert in that routine is veritying that we have exited edit mode (or more accurately that we don't still have a CVP for a cell in edit mode which would/should have been cleared when the cell exited edit mode unless there was a problem there or unless someone tried to force the cell back into edit mode likely on another cell). That may well have been happening in your real application without you knowing since you would only see the assert if you were using a debug build - which you weren't with the release version.

I'm not sure what you are asking. If you are asking about when GetChildrenCore will be invoked as I mentioned I do not know as that is not something that we control. It is controlled/invoked by the WPF framework when something wants to get the children for a given automation peer or possibly when the associated element has been invalidated to update the cache. For anything further on that method you would have to check with MS or use reflector to review the WPF framework's implementation.

As to the OnSorted that is used to raise the Sorted event and from your description I do not know what is the cause of the NRE - it could be within your handling of the Sorted event or something else.