One of the most challenging thing when programming is to have proper error handling. This is one of the weakness of the standard NAV code. We are now seeing this change when Microsoft introduced the simplified NAV.
An example of this can be found in report 1306.
Here Microsoft have created a dedicated function for error handling.
This type of error handling will tell the user what the problem is and how to fix that problem.
The flow is; when printing the invoice NAV checks to see if payment information has been entered into the Company Information table. If not a question will be asked if the user wants to update the payment information. If the user agrees then the Company Information page will be displayed and the invoice printing will continue after that page is closed.
I wanted to adapt to this method – perhaps a new error handling pattern – when I write an add-on or a customization.  Here is an video from Mark Brummel in line with this new pattern.
I have added this kind of error handling but in some cases a little bit more is required.  As an example, I am doing a series of tests when the Payment Method Code is validated in a Sales Header.  The problem here is that NAV is in the middle of a transaction when I have that question to ask.
To solve this I use a function that is intended for testing only, so using it is not really supported by Microsoft. Perhaps, if they read this blog they will see a useful application for this function in the standard solution.
Here I have two options for you to consider. Doing an ASSERTERROR ERROR(”) will rollback the transaction without stopping the code execution. By doing this before the CONFIRM question I make sure that the users will not be blocking the database while deciding what to do.
Pressing Yes will open the page.
After fixing this error the user can retry the previous action.  I will most likely use a code like this.
Use this carefully.