Hi all. Old dryer line here, S7-315-2 DP, STEP 7 V5.5 SP4, project from 2009 that four of us share. A colleague added an FM 350-1 to the rack last week and since then nobody can open the hardware config.
The dialog says "This object was not found." and down in the bottom corner of it, small, there is "256:31". That's the whole message, no block number, no address, nothing else.
I closed SIMATIC Manager and reopened it, restarted the PC, and copied the project to another machine and tried there. Same dialog every time. I've been searching for two days and I'm stuck. Every S7 error code list I find is OB numbers and CPU LED patterns, and not one of them has anything that looks like 256:31 in it.
Does that number mean anything to anyone, or is it one Siemens never wrote down?
Two things before anyone guesses. What exactly were you doing when it came up, opening HW Config from the Manager or compiling it, and is the number in the title bar of the dialog or only in the corner?
Where does the project actually live. Local disk or a share that all four of you have open at once?
Opening HW Config from the Manager, double click on Hardware. It never gets as far as drawing the rack. The number is only in the corner, the title bar just says SIMATIC Manager.
Project's on a share, all four of us work straight off it. I had the symbol table open in another window when it first happened, not sure if that matters. Also the colleague who added the FM 350-1 did a Save As on the project a few weeks before that, I only found that out this morning.
Work off a local copy, not the share. That clears half of these.
Already did that on Friday, and again this morning with everyone else out of the project. Copied the whole folder to C: on my own machine, opened it there, and it's the same dialog and the same 256:31.
You can't find it because you're searching the wrong family. A code with 256 in front of the colon is a SIMATIC Manager message number, not a CPU event and not a block error, so no diagnostic buffer list will ever carry it. The 34 family is the compiler, the 88 family is the online connection.
256:31 says the object it went looking for isn't there, and the reason given is that the address assignments in the offline database no longer agree with the hardware config. A Save As with reorganisation rebuilds that, and everything has to be closed first or it quietly does nothing. The list with these numbers in it is here: https://plctr.com/siemens-s7-plc-error-codes-and-causes-solutions/
That was it. The offline database had lost its address assignments against the hardware, almost certainly from the Save As the colleague did, and HW Config was falling over before it could draw anything.
The key combination in that list, Ctrl Alt F11, did nothing I could see. What worked was File, Save As, with reorganisation ticked, every editor and the symbol table closed, and the other three logged out of the project. Took about nine minutes on the share. New project opens straight into HW Config and the FM 350-1 is sitting there in slot 5 where he put it.
What I still don't know is whether it was his Save As or the module that broke it, and I'm not going to find out on a live line. Thanks pnina and hkraus.
Good one to write on the cabinet door. Nobody ever remembers the 256 family exists.