Trying to Download a RS Logix 5000 program to a 1756-L62-Following Errors

Good Morning ,

I received a used 1756-L62 / A CPU , from a vendor that was using it for a trainer. I tried to download a program that is being used on the plant floor that is using a 1756-L62 / B . I get the following errors when I try to download.......

Creating all 'Batching_Station_1' Tags...
Creating all 'Batching_Station_10' Tags...
Error: Reply buffer invalid.
Error: Failed to create Programs and Add-On Instructions.
Complete - 2 error(s), 4 warning(s)

The program has a number of Add-On's , and using ControlNet . Do you need to load anything separately , such as the Add-On's , etc. What would these errors mean ?

Thanks as always for your help,

I don't remember differences by heart, if you go into the tech documentation and the release notes of the firmware, if there is anything, it will be there.

Are you sure, you have the same firmware revision on your application and the controller?

Are you using a 1756-ENBT by chance? If so take a look at Tech Note 61910.

The solution from the Tech Note is to replace the 1756-ENBT module.

No. Directly to the CPU via Serial 1747-CP3 cable

Program is 20.11
1756-L62 current revision is 20.011