Primary Workbook & Secondary / linked workbook

Hi -

This could be possible, depending on how you structure the two files. First, you have to restrict the amount of freedom the client has to make changes to their data file. For example, they can only enter data in certain rows or columns. That way your master file is looking at the same places. Second, unless their computer system is exactly mapped like yours, the updated master file may have difficulty finding the data file. The paths have to be exactly the same. I suppose you could use VBA to run a routine that allows the user to give your master file the correct path to the data file, but that is out of my league. But, if the systems are simple (i.e., C:\datafile.xls, then it could be done. If you have clients with a server, so the data file could be on Drive G, F, X, whatever, that's going to be a problem.

Assuming you can get past those hurdles, you would probably need to use dynamic range names (ranges in the data file that expand automatically to the amount of data the user has input). That way, the formulas are just looking for a range name in the data file rather than a specific range (A1:G275) for example. Finally, it kind of depends on what your formulas and functions are doing with the data. Some functions play well with remote files, some can be a struggle.

Hope that helps.