Nicky
If the file was saved as a new name, the original will still be on your
computer.
If it was saved as the same name, it has been over-written and unless you have
a backup you are outta luck.
Do you have "Always create a backup" checked under File>Save As>Tools>General
Options checked?
If so, look for a *.XLK
The backup is one save behind the current save.
Gord Dibben Excel MVP