File/ Save As/ Tools/ General Options/ Always create backup
will save a backup, so you will have one previous version, but the safest
bet is to save as a different file name each time.
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David Biddulph

Crissyb wrote:
Can you save a file in the same filename and still retain the earlier
revisions? Someone accidently overwrote a file and should have kept
the earler versions.Is there something in Excel that I can turn on so
my main filename only changes with an extension, therefore keeping
all my earlier revisions? i.e. 'filenameX'.xls1 'filenameX'.xls2 so
everytime I save it to 'filenameX', Excel is adding a new revision
number automatically so I don't loose revisions or accidentily wipe
out good data. Help!