System.Collections.Generic.KeyNotFoundException

@Darcy Brown
likely due to custom question you are asking is a table entry and the table entry is inactive or deleted in the table. check that first

@Darcy Brown
From the error message it sounds like the problem is what I posted.

So check the online express form (donation or registration one that is causing this) and see if you are asking custom question or not. if yes, then check if it is question based on an attribute that is table entries values (choice/drop down selection), if yes, just save the form and all “new/changed” entries will be uploaded and issue resolved.

if not, contact blackbaud support with the error