What does it mean by "line <some number> of part" in Creo Parametric?

[Hidetaka]

I am creating a family table with some parameters being driven by relations and get this notification after regenerate any instance. (it is not an error or a warning, I can regenerate the part without any problems.)

It is mysterious to me. Initially I thought the line number means the line in the Program, so I opened it, but there was nothing at line 30. 

I tried a lot of things, and finally when I delete this line in "Relation", the above notification disappears.

PTC_COMMON_NAME = SOME_STRING_PARAMETER

It seems that the above line is the culprit of that notification/warning, but when I verify the relations, that line does not cause any problems.

Could someone please tell me what does it mean by "line" in the notification in the screenshot?

Thank you very much! 

[TomU]

"Line 30" definitely refers to a relations line.

What is "SOME_STRING_PARAMETER" set to?

[Hidetaka]

It is just a string (it is different for each instance in the family table.)

I also thought that line 30 is either line 30 in Relation or Program, but my relation part doesn't even have 30 lines. 

[pausob · Accepted solution]

I think PTC_COMMON_NAME can only be assigned a value via relations for new objects.  After upload / check-in of the part to the Windchill server, this special parameter is basically locked (software will internally assign it the value of the Windchill "Name" field") - and attempting to assign it a value via relations will result in this cryptic error.

[Hidetaka]

Thank you for your answer. After that relation was deleted, the "invalid assignment" warning also disappeared.

The only thing I still don't understand is that number 30. I have less than 30 line in the relation windows, and there is nothing at line 30 in Program.

[TC_9326942]

Another potential solution...I have also seen this error when a part relation tries to assign a value to a parameter that is already defined (in my case its a declared layout where this parameter is first defined).  Upon part regen, the system says "Line 126 part XXXXXXX: Invalid left side of assignment".  As soon as I deleted the extra set of relations in my part, this error went away.  Just like you, I have no idea what/where Line 126 is as it doesn't correspond to any line in the relations or program that I can tell - the error notice also shows in the relations right below that extra relation assignment.  Note this message also appeared in the assembly that uses this part as well.  Hope this helps.