Sometimes, when you run the Moxa PRP Setting tool, you might see the following error message because of which the expansion module card cannot be used.
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This issue occurs because Windows OS does not have the registry entry ModelName for DA-820C resulting in the computer not being able to detect the PRP/HSR expansion card.
To solve this issue, add a registry entry in Windows as described below:
1. Open the Windows registry and go to the path: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\MOXA
2. Create a new registry entry ModelName with the value DA-820C
3. Restart the computer.
The PRP utility will now be able to detect the PRP/HSR card.