Advanced macro format required

Using variables requires that you use the advanced macro format for your macro (see Choosing a macro format). Therefore, if you want to add variables to a macro that is in the basic macro format, you must decide whether to convert the macro to the advanced macro format. If you have an old macro in the basic macro format that many users rely on and that works perfectly, you might want to leave the macro as it is.

However, remember that all recorded macros are recorded in the basic macro format. So, if you have recently recorded a macro and are beginning to develop it further, then you might simply not have gotten around to switching to the advanced macro format.

The Macro Editor addresses both these situations by popping up a window with the following message when you start to define a variable in a macro that is still in the basic macro format:
Figure 1. Reminder message
You are attempting to use an advanced macro feature. If you choose to continue,
your macro will automatically be converted to advanced macro format. Would you
like to continue?
Click Yes if you are building a macro in which you plan to use variables, or No if you have a macro in the basic macro format that you do not want to convert.