Troubleshooting: Trajectory Processing fails when multiple observations are added from different base stations

📌 Problem

Trajectory Processing fails and the Job Manager reports the following error:
Note: The error mentions the .PosT file since it is the sbet format for the TV540. For other sensors it may mention the .out sbet format.

Error adding NAV file(s): Could not download a navigation file.
Could not download a navigation file.
Unable to locate the *.PosT file below the folder:
C:\_LP360Projects\_TempLP360\...\POST

🔍 Root Cause

A sbet (.PosT or .out) file is only created when Trajectory Processing successfully generates a trajectory solution.

One common cause of this error is the use of base observation files collected from different base station locations in the same processing job. While multiple observation files are supported, they must originate from the same base station.

When observation files from different base stations are combined, trajectory processing fails since the sbet file is not created.

🧠 What is a sbet File?

The sbet (Smoothed Best Estimate Trajectory) file contains the processed trajectory solution used by downstream workflows. If trajectory processing cannot complete successfully, the file is never generated, resulting in the "Unable to locate the *.PosT file" error.

✅ Probable Resolutions

1. Verify Base Observation Files

Confirm that all observation files used in the trajectory processing job were collected from the same base station location.

1. Review the observation files assigned to the project.
2. Verify that all files originate from the same base station.
3. Remove any files collected from a different base station.
4. Re-run Trajectory Processing.

2. Process Each Base Station Separately

If the project contains observation files from multiple base stations:

1. Group the observation files by base station.
2. Create a separate trajectory processing job for each group.
3. Process each group independently.

📚 Additional Notes

• Multiple observation files are supported when they originate from the same base station location.
• Supported observation formats include RINEX, T02, T04, and other supported GNSS observation formats.
• Combining observation files from different base stations in a single trajectory processing job is not supported.
• The missing sbet file is typically a symptom of a failed trajectory solution rather than the primary error.

📬 Need Help?

If you're still stuck, please Contact Support for assistance.