• C# Create Sales Invoice From Sales Order; nSetKey() fails, sLastErrorMsg = "The [InvoiceNo] is invalid"

    I am on Sage 100c Standard 2016 (Version 5.30.5.0) (yes, I know it is very old, and have plans to upgrade to a supported version). I am attempting to create a program in C# that creates a sales invoice from a sales order. When my program executes the…