Hi,

I have a standard program that is used in several different similar machines. The hardware is the same in all machines. Communication via PROFINET.

I downloaded the project into the PLC, and there were complaints from the CPU that the version in the HMI panel was too old (V15.1.0). So I updated the operative in the panel to v17.0.0.0.
I then had to download everything, the HMI panel showed images but there were hashtags on all the values ​​that should be displayed.

From what i can see i have communication between CPU and HMI. IP number and hardware configuration appear to be correct.

If I go online on the PLC, I see that the values ​​are alive.

HMI tags appear to be correct, with correct connection. I have tried to make a new connection between PLC and HMI without result.

Tried a synchronization of WinCC tags without result.

in network view everything is connected. Is an HMI connection needed in the Topology view? Because it makes no difference in this case.

Do you have any tips on what else I can look at that might be wrong?
I don't get any error messages.

Feel free to ask follow-up questions.

TIA 17

CPU:
1512SP F-1 PN
6ES7 512-1SK01-0AB0
V2.9

HMI:
TP900 Comfort
V17.0.0.0

and has the following alarms:
140001 Connection disconnected: HMI_Connection_1, Station  [ip.nr], Rack 0, Slot 1

Secure PG/PC and HMI communication is off in CPU

AutoGen_6185438

Thanks for the reply.

I activated the alarm buffer in the alarm list.

and has the following alarms:
140001 Connection disconnected: HMI_Connection_1, Station  [ip.nr], Rack 0, Slot 1

Secure PG/PC and HMI communication is off in CPU

It sounds as if you are already following the directive given in the article..
Why is it not possible to establish a connection to a CPU with firmware version 2.9/4.5 from an HMI panel (Basic, Comfort or Unified) or WinCC Runtime Advanced V17 or lower? 

Did you make 100% sure that you loaded the hardware configuration? The PLC name should be highlighted when doing a download. Some people confess on the forum to have only downloaded the software part.

As a sanity test make a new small project. Set the CPU firmware as V2.8 in the hardware configuration, but leave the actual loaded firmware as is. Have the minimum functionality to test the link of CPU and HMI. Do you still have problems?

Follow up by updating the firmware in the hardware configuration to match the V2.9 firmware in the device. Test again.

If you still are faced with problems, consider using the "Support Request" link to also chat with Siemens. Please do let us know on the users' forum what your findings are.

Good luck.

don't know if it had something to do with the secure connections. we brought over an old backup and unchecked everything with secure connection. Then it works.

If you look under the connections on the HMI in the project, there is the "access password" field for the PLC under the IP number. Should a possible password for the secure connection be entered there in that case? Shouldn't the HMI or CPU complain that this password is missing?

Anyway, we've got the machine running. Thank you so much for your input.