I think i will just let this go, Cetin.
Thanks for taking up so much of your time.
I have been helped greatly by your replies to other threads over the years.
I was just hoping someone had come across a situation where a property (or any object member for that matter) in one context was not found in another, aside from calling RemoveProperty().

kindest regards

Barry,
Sorry but you are hiding the actual code.
Here discount is referred to in SetupData() but not in createLines() as I see it.
We don't know what a_soimp and lo_line is. a_soimp might be an alias, or a memory variable pointing to an object (which in that case should be prefixed with m. to be safe - otherwise it is a source for error).

Error might be referring to a_soimp (if that is a variable) or lo_line 'xxx' property is not found. We don't see what they are and the actual code creating and using these.

>Thanks Thomas, I take your point.
>Below is the relevent code.
>Notice that "discount" is in the class constructor, and occurs in SetupData() and CreateLines() respectively.
>It does not complain in SetupData() which executes first but, but throws an exception in CreateLines() which executes immediately afterwards.
>But only in runtime does it throw an exception.
>
>

>DEFINE CLASS tdbflink AS tmessagelink
>
>	saveenvtries = 0
>	*/BarryT 07/17/2019 09:46:32 AM START 
>	discode = ""
>	discount = 0.00
>	*\BarryT 07/17/2019 09:46:35 AM END 
>	Name = "tdbflink"
>
>	PROCEDURE set
>		*-- we are on a new order, so create what we need, and save the info that we want
>		this.setupdata()
>		*-- Create all the necessary line items.
>		 this.createlines()
>
>	 ENDPROC
>
>
>	PROCEDURE setupdata
>		*-- Setupdata()
>		*-- get the standard stuff
>
> 		*/BarryT 07-17-2019 11:22:44 AM START
>		THIS.discode = Alltrim(a_soimp.discode)
>		THIS.discount = a_soimp.disc
>		*\BarryT 07-17-2019 11:22:45 AM END 
>
>	ENDPROC
>
>
>	PROCEDURE createlines
>		*-- Create lines for each of the order lines in this file.
>
>		        */BarryT 07-17-2019 12:37:17 PM START
>		        lo_line.discount = a_soimp.disc
>		        lo_line.discode = a_soimp.discode
>		        *\BarryT 07-17-2019 12:37:19 PM END 
>
>	ENDPROC
>
>ENDDEFINE
>

>