Module Configuration Rejected... why?

I have two AB 1769-OW8I/B digital output cards on a remote rack that are giving me the following fault:

(Code 16#0009) Module Configuration Rejected: Parameter Error.
Additional Fault Code 16#0401

No way to clear the fault except power cycling the rack. I have two identical process lines running the same equipment in the same configuration, but it's only this one I have the problem on. Thoughts? If anyone has a fault code list for this module, you'd be my hero for sharing it, since I can't make heads or tails of what I'm seeing.

Different revisions? I've had it happen to me.

I don't have the RSLogix5000 software right now so can't post any screenshots. But the first thing I would do is go online with the PLC, go to the Controller Tags, and look at the Controller Tags for these modules. There could be error/status bits that give you more info.

Also, while online with the PLC, find these modules in the IO Configuration, right click on them, and carefully look at the popup window with the Module Properties.

Since you have identical systems that are working fine, try going online with the PLC in these identical systems and comparing to those.

Another thing to look into is the firmware revision of the modules, as dcam mentioned. Compare the firmware to that of the modules in your identical systems.

If possible, swap these problem modules with the ones in your identical systems (may not be possible if you're running production)

I just searched online for error codes for the 1769-OW8I but couldn't find anything but this manual, which does not have much info:

https://literature.rockwellautomation.com/idc/groups/literature/documents/in/1769-in053_-en-p.pdf

Hope some of these suggestions help.