Thank you for your advice. I may need to explain the problem a little better. When I created the five extra spreadsheets, they are identical to all the others, and are included in the formulas that add up on the Master Production spreadsheet. For instance, my formula will sum a column from spreadsheets named, Jane, John, Mike, Mary, File A, File B, File C, etc. When I new employee begins I need to take File A and rename it, but without interrupting the formula. So, when I rename the file, I then go into Edit>Links and try to "change the source" of File A to the new employee's name, I am then given the error message "formula too long." Is it not possible to change the name of a source file without destrying the formula in the destination file? Unfortunately I cannot put all of the spreadsheets in one workbook, because each employee keeps their production report on their computer. And in each employee's file is a tab for each month. Thank you again for your help!