There is a system map file for each "project". If you started writing a new program then a new, blank system map is created along with it. If you want to keep your first program's system map, then copy the first program's .prj file over the .prj of your new program and it will now show you the names and modules you had created the first time.
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"If you don't know what you're doing, do it neatly..."
