As far as I know, the only thing in the program that can "affect" a credit limit is the user changing it. So can you give us an idea of how the quotes are affecting the credit limit?

When a customer has outstanding invoices totalling more than the limit, there is a message that pop up but that does not affect the limit in my mind.

If you are getting these messages as you do quotes for the customer, the program is probably working as it is designed and warning you that the customer should not be sold to until they bring their outstanding balance below it. I am assuming here however, that the customer also has outstanding invoice dollar amounts greater than the limit.

Sage 50 Canadian has no controls that prevent creating a Sales Invoice, there is only a warning at invoice creation time for a customer with outstanding invoices > the credit limit field.

So I'm left with the conclusion that you are not using Sage 50 Canadian, and this question would better be posted in another Sage forum.

If you're the water treatment company in Winder, Georgia, USA, then definitely not Sage 50 Canadian.