Multiple users updating one excel spreadsheet
But no matter what, you'll never lose anything because of Page Versions (revision history).
S Have a look here for further info Try having one sheet updated by the sheets they are using.
At the beginning of the day, their respective sheets can be populated by the master, then at the end of the day, their work can append to the master.
Many thanks Excel 2007 Win 7 PC Shared spreadsheets are a nasty hack that IMO are best avoided and never work properly.
The long and short of it is that Excel just isn't designed for multi-user access.