The object cannot be modified because the status for this object is not "Working". If you have permission then you can change the status to "Working" on the properties dialog - Intergraph Smart 3D - Troubleshooting

Intergraph Smart 3D Troubleshooting Reference

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English
Product
Intergraph Smart 3D
Subproduct
Troubleshooting
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Troubleshooting
Smart 3D Version
11 (2016)

Meaning: If you create or modify a trench run that has a connected trench run, and the connected trench run's status is not Working, an error occurs.

Recovery: Edit the status of the connected trench run to Working, and then update the trench run.