Hi everyone,
I'm having an urgent issue with a Siemens S7-1200 PLC: I'm unable to download my program from TIA Portal to the PLC.

I keep getting the error messages shown in the attached screenshot(s).
Has anyone encountered this issue before or knows how to fix it?

Any help would be greatly appreciated — thanks in advance!

I performed an online diagnostic of the PLC using TIA Portal.
I can see that the PLC is in STOP mode, which is also confirmed visually on the HMI (no activity, clearly stopped).
Additionally, the PLC’s memory appears to be empty— is shown as 0, as seen in the attached screenshot.

Does anyone know what might cause this situation or how to properly restart the PLC in this state?

Thanks again for your help!

0_Einstein

When you checked the plc diagnostics buffer for the reason the plc went into stop mode, what did you find?

 Here is what I found when I diagnosed my PLC, specifically in the diagnostics buffer.

0_Einstein

I recommend downloading and installing the latest available firmware for your PLC.  That may well fix the problems with your PLC.

 Thanks for the suggestion. I did update the firmware as recommended, and I was able to switch the PLC to RUN mode — it worked for about one second, but then it stopped again. So unfortunately, the issue is still not resolved.

0_Einstein

What was the reason in the diag buffer the plc went to stop mode?

Does your PLC logic have an OB80 Diag Error Interrupt OB?  If not, please add one.

 I already have OB82 in my program. Do you think I should also add OB80?

OB80 is one of those that you should have in every project. 

What is the PLC's stop cause in the diagnostics buffer?

Hati

OB80 is one of those that you should have in every project. 

What is the PLC's stop cause in the diagnostics buffer?

You're right, OB80 is definitely one of the blocks that should be included.

However, in my case, I believe the PLC memory has been completely wiped— there’s no program left inside, and it’s no longer accessible for loading a new one.

Even if I try to add OB80 and download the project again, I get thesame error(see attached screenshot). That was actually the last time the PLC communicated properly and accepted a download.

Do you think there’s a way to recover it in this state?