first things first ...
I'm in middle of full production offshore and cannot stop plc
if everything is running OK – then I recommend that you just let it keep running until you ARE allowed to stop production ...
I noticed in online there is acrung with error (e on left side of rung).
the "lower case e" does not stand for "error" – it stands for "edit" – which basically means that the rung is capable of being "edited" (or changed) ... the fact that the "e" is in lower-case (not a CAPITAL letter) means that the changes to the "e" rung which are shown on the programming screen are not yet registered (or present) inside the PLC processor ...
in simplest terms, since the "e" rung is NOT actually inside the PLC processor, then it shouldn't be causing any problems with your production ... that's basically why I recommend that you just leave it alone until things settle down ...
in simplest terms, the PLC processor does NOT even know that the "e" rung exists ... the PLC doesn't see the "e" rung ... the "e" rung is not affecting the operation of the PLC ...
I cannot delete this rung
you can probably "Cancel" it though ...
If I try to delete and accept changes it doesn't allow me
in Rockwell software, the word "Accept" does not mean what most people think it means ... specifically, in English the word "accept" usually means to "take" or to "receive" ... in Rockwell software the word "accept" means to "SEND" ... specifically, when you "accept" a rung, you are not "taking it" – instead you are actually SENDING it to the PLC processor ...
so ...
if the rung has an error (for example: an UNKNOWN instruction) then the RSLogix software will NOT allow you to SEND/ACCEPT the rung ... specifically, you are not allowed to SEND a defective rung to the PLC ...
I'm just GUESSING – but that's probably what is happening in your situation ... specifically, you can't SEND/ACCEPT the rung – but you might be able to CANCEL it ...
WARNING!
from what you've posted, I am afraid that you also have OTHER edits/changes (beside the "e" rung) that have already been accepted (sent) to the PLC – and that those other edits/changes are being TESTED ... if that is correct, by messing around with that "e" rung, you could possibly UNTEST those other edits/changes ... if you do that, then your PLC's operation is going to change (possibly drastically) and your production could suddenly be interrupted ... that would be "bad" ...
DISCLAIMER: we can't see what's on your screen ... we're doing the best that we can to answer your questions – but a lot of what we're doing is GUESSING about what you're seeing – and about how you're describing the situation ...
I strongly recommend that you post a full screen shot of your situation ... I cannot stress enough – IF THE SYSTEM IS RUNNING OK – THEN LET IT KEEP RUNNING UNTIL IT BECOMES SAFE TO SHUT DOWN PRODUCTION ...