unity pro io module internal error

Hi Adem,
It is likely a power or wiring problem with your IO module. If Unity Pro Diagnostic Viewer isn't giving you more details, it would be recommended to contact Schneider Electric support to get additional help. The module itself may have failed, so best to check if it needs replacement.

You tagged your question with "BMEH1020" which makes me think you are using a Hot Standby configuration. If so, are you sure you have configured your I/O racks in such a way that your setup is able to handle the I/O redundantly? For example by using them as Remote I/O instead of placing I/O modules in the main rack.

Other than that, this is not a Schneider Electric nor a PLC forum, so your best chance for a solution might be contacting Schneider support, like Olivier mentioned.

Hi Adem , will you please share the complete details about your . So that we can understand your scenario.
Mainly your system architecture.