AmyC and others:
I believe that I have found the answer to my problem in attempting to efile my Nebraska state return and it appears to be successful. I will provide my solution here for others who may have encountered a similar problem. Nebraska unfortunately has two different systems for numbering counties. The most common is the one that appears on auto license plates and is based on historical population. The system of county numbering is one that is used by some state departments and is alphabetical. I initially used the most common county numbering system when I entered data in my state return. At one point the software just asks for the county number and provides only a picklist of numbers (with no county name for a reference). At that point I had entered (02) from the Lancaster County license plate. Upon reviewing my draft return in an attempt to problem solve my error loop related to the Property Tax Credit, I re-encountered this county number question (with only the numbered picklist). So I thought, let's try the alphabetical number (55) instead. And with that change the software error disappeared and the state efile worked.
