Hi @ABraun, the error I was reporting is related to the ALOS CEOS using SNAP version 6.0 and also version 7.0 on Windows (but it looks like you have proved that the ALOS GeoTIFF import does not work either!).
What would you recommend in order to be able to process ALOS CEOS or GeoTIFF L1.5 since SNAP 7.0 does not work?
I tested the CEOS data as well now. I imported the data via File > Menu > Import > SAR Sensors > ALOS-2 CEOS and was able to load and display it correctly in SNAP 7
Have you installed all updates (Help > Check for Updates)?