I created a list in SharePoint 2013. See detail information below.
Title: not required, but enforced unique
State: lookup, required
County: lookup, required
I create a workflow, to set Title as 'State'-'County'. If user enter an duplicate item, e.g. CA-Orange is already existed in the list, there is an error happening.
1. How to check if an error is happening and pop up a warning to user? For my case, how to check it the data entry is duplicated?
2. How to set the error message in Nintex workflow?