Good Morning everyone .

I have a TIA Portal V18 project with an S7-1212 PLC and two HMIs: a KTP1000 Basic Color PN (Firmware V12) and a KTP700 Basic PN (Firmware V17). Everything was working fine, but I upgraded the PLC to an S7-1214 with Firmware V4.5 to add more inputs.

After the change, both HMIs were visible and I could connect to them, but they weren't exchanging data with the PLC. I disabled the setting "Only allow secure PG/PC and HMI communication" and enabled "Permit access with PUT/GET communication from remote partner" on the PLC. After that, the KTP1000 started working correctly, but the KTP700 still doesn't.

I read somewhere that time synchronization might be required. After some tests, I'm now unable to connect to the KTP700 to download the program — it shows "Not reachable."

Maybe I should consider resetting the KTP700.

I'm not sure how to proceed. I would appreciate your assistance.
Thank you inn advance!!!

Hello,

Thank you for your swift response!!!

After syncing the time with the PLC, may have accidentally reset the IP settings of the HMI while trying different solutions to make it work.
After setting the IPv4 IP address, subnet, etc., in both Windows and the HMI, all devices are now detected correctly, and the HMI is successfully exchanging data with the PLC (this may be due to the time synchronization).