I don't know if anybody has run into this problem, but what do we do if an address does not return any matches in the US Census system in regards to the County Code and Census Tract #?

Pull out a map.

I pull the address on a google map or use the map provided in the appraisal, locate that same position on the FFIEC map and pinpoint it. I retain a copy of the google map or map provided in the appraisal in the loan file to support the data I'm reporting.

Ditto with Randy and LaLendingLady. Sometimes Googlemaps finds it where the other site does not.

Just so we are on the same page, we are talking about the new 5 and 11 digit code, right?

I just wanted to follow up on this one, as I had another property that wouldn't pull up in the Census Bureau website.

Has anyone yet addressed where we get the new 5 digit county code and the 11 digit census tract number? I am not able to find those anywhere.

Still https://geomap.ffiec.gov/FFIECGeocMap/GeocodeMap1.aspx

I believe the 5 digit is a combo of the state and county codes and the 11 digit is a combo of the msa and census tract codes.

The county code is the 2-digit state + 3-digit county
The census tract code is the 2-digit state + 3-digit county + 6-digit tract excluding decimals

LaLendingLady is correct.
Seems odd that they added the 5 digits to the census tract when we report those same 5 digits for the county.