the 'other' file is a SKP file, and has been operating independently for weeks, and then all of a sudden, it has started opening itself whenever i open other SKP files (not all of them), so I get a twofer.
And I can't close the piggyback SKP file without forcing.
all of my SKP files were created from a default template, but they do share a lot of the same components (nothing new that i haven't used before).
thanks for the info