Do you have any non-Beckhoff FSoE devices in your safety? Like Rexroth IndraDrive with FSoE, robot with FSoE etc.
I didn't check it in detail, but last year I had something similar and it looks like TwinSAFE is working with the ESI files (EtherCAT XML files in C:\TwinCAT\3.1\Config\Io\EtherCAT ) on your laptop and does not save the ESI information inside the project. That means if you install new ESI files for new projects on your laptop, it can happen that you cannot edit old safety projects anymore.
For normal EtherCAT slaves the ESI file on your laptop is used only once when adding the device to the bus/project. TwinCAT then saves the ESI information inside the project. Therefore everybody can open/edit the project although the ESI files are missing on the laptop.
Conclusion: Install the ESI files from the Std with this function and execute this function everytime you get an old project with TwinSAFE:
If you have only Beckhoff devices in TwinSAFE, then it will be more difficult because the (old) Beckhoff ESI files are not included in the Std.
One day TwinSAFE will also get a Remote Manager functionality, then this problem should be solved ...
... View more