All great questions Ronny - we will need all of the details of when and how this is happening Jeff - can you provide ome more context
1) How is your site coordinated - is it Coordinate System only (Projection and Datum) or is it with a localization as well (Site Calibration) or is it only a Site Calibration? If you are using a Coordinate System can you provide the details of which one - complete settings will be required to recreate the problem. If you have a Site Calibration can you also provide that to me to look at.
2) Are you using a Geoid - If Yes - which one. Are you using the whole Geoid or have you subgridded it?
3) Site Calibration - what was used to measure theSite Calibration - was it SCS900, Siteworks, Access or did you use Coordinate Pairs in TBC (XYZ and LLH Pairs)
4) What workflow process in TBC is throwing the error - is it the Export command using the Machine FIle Exporter or is it the Create Site, Design, Work Order Process or the Publish to Library command or Works Manager process where the problem occurs
5) What type of Machine System are you exporting for i.e. GCS900, Earthworks and which Version of the system are you exporting to (GCS900).
6) Can you share the Project data where this is all defined so I can take a look at the process to recreate what you are seeing and then I will see if I can find a solution for you today.
I will do what I can to assist or find you an answer
Alan