InfoPath Dev

Hi there,

this is my first post and my english is just quite good. Please forgive me for my diction.

Here is the situation, where I need your help. I have two SharePoint lists.

1. ListA (Column1 = ApprovalGroup)
2. ListB (Column1 = ExceptionType, Column2 = Tier1, Column3 = Tier2, Column4 = Tier3, Column5= ApprovalGroup)

The amount of the Column1 items in the SP ListA is much more than the amount of Column5 items from the SP ListB. But some of the values are exactly the same.

In InfoPath form I have 4 Cascading Dropdown list and one multiselect list, named MultiListC.
This MultiListC should only display those values, which are listed in SP ListA, but not in SP ListB.

My question at this point is, how can I use one or more rules with filtering in InfoPath for the MultiListC multiselect list, so that only those value should be diplay, that are existing in ListA, but not in ListB.

Please don't forget, that the Column5 Values are dependence on the cascading dropdown value from the SP ListB (ExceptionType, Tier1, Tier2, Tier3).

My Idea for filtering was: MultiSelectC = ApprovalGroup(ListA) is not contain ApprvalGroup(ListB) where ExceptionType = DDL1 and Tier1 = DDL2 and Tier2 = DDL3 and Tier3 = DDL4.

Unfortunataly, this doesnt work as I was expected it. It only remove the first Value from the SP ListB, the other values are still displayed.

Could someone help me or give me feedback, please?

 Thanks in advance,

Cheers

dogi80