Hi Flip,

I usually use another GlobalValue, named something like "Prefix" for things like this. I make a Settings Form with nothing but unbound elements that allows user to edit the various settings and save them by clicking a button.

If this is going to change yearly, can't you make the prefix a function of the current year?
So it will automatically change at the beginning of the year, and would be correct all year long. 
No need to change it every year.

A variation of the following:

varIncrementalNumber = Existing Sequential Number
GlobalVariable("NextNumber",@Str(@Year(PurchaseOrderDate)) + @Str(varIncrementalNumber)) 

For the varIncrementalNumber, you could have an Invisible, ReadOnly auto incrementing element on your purchase order form.

There are a number of examples on the forum on how to do this using @XLR and adding 1 to the value.  Used in place of @Number

Also check the Sesame Programming Guide, page 59, for an example of using @GlobalValue instead of @Number.  Just modify that example to add @Year(PODate) to the front as shown above.

Not quite sure when you are setting this value, but would suspect it would be on New Records.

But your programming will never work, because you @Modified will never be true it @IsNew is True, so that programming will never be executed.  I think you may want to remove the IF @Modified section, or change the conditions.

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Edited....My above statement is incorrect.

I am probably suffering from my Q&A history. 
I understood that this was a Q&A carryover, which could only occur once a record was already saved. 
According to Mark, Sesame is a little different.

He is correct.   
In Sesame the comparison is made against the form content when is it first shown, vs.  comparing against a record content.

From the Sesame Programming Guide, page 189: Quote:

So, in Sesame it is possible to have @IsNew and @Modified both True at the same time. 

Sorry for any confusion.  Still learning something new about Sesame every day. 

Thanks to Mark for the clarification.

Hello Mark,
What I posted works fine, but I understand what you mean, it is posted on an element exit. What I am looking for is to lookup a field on the setting form and us it as the prefix on the number. Seems I cant xlookup without a key field.

I have a couple other applications I could use this on as well

I appreciate everyone’s help!

At the least, the date comparison is failing because it needs double quotes:

 If odate >= "1/1/2007"
 

If you do not double quote it, SBasic believes you are trying to divide 1 by 1 by 2007.

Try temporarily inserting a bunch of writeln statements into your program, to see what's happening.