CHIRP

New to two way radios. I have two Baofeng BF-888S and two Baofeng BF-888S Plus that I have been able to connect to via an Amcrest FTDI cable. Using CHIRP, programmed them all so they are able to communicate with each other. However, I uploaded an edited img file ( and downloaded same one immediately) to one of the units and it seemed to be ok. Tried to upload the same img to the other units, but now can't communicate via CHIRP with any of the units. All return an error message "An error has occurred - No response from radio" when trying to "Download from radio" or "Upload to radio" with an img. Port, Vendor and Model fields all appropriate. Driver correct and registers under Ports (COM5). Incidentally, the other 3 units still able to communicate with each other.

Any help would be appreciated.

Thanks,
Leo