We are having the same issue. Since this issue seems to deal with GPS Analyst and not the GeoXH specifically, I have started a new posting:
A summary of the posting is below
We are crashing GPS Analyst everytime we attempt to postprocess data. Our configuration is as follows:
1. Trimble GeoXH, ArcPad & GPS Correct
2. ArcGIS 9.1 (Service Pack #2)
3. Trimble GPS Analyst 2.0
When we start postprocessing data using GPS Analyst, the differential correction wizard window activates and we move through the menu options. After selecting the base data provider and starting the data postprocessing, our ArcMap session crashes. Any thoughts?