Hello Steven

While I'm not directly answering your question on how to create a
notification that a workbook is already open, I wonder out loud if a shared
workbook wouldn't better meet your needs? This way two people can edit the
worksheet at the same time and the changes are all merged. There comes a
"hiccup" when the two edit the same cell at the same time, however, you can
"resolve conflicts" in shared workbooks as well so that they can accept the
other person's change over theirs or keep their own change.

I'm not sure what version of Excel you are using so if you type "share a
workbook" in your help dialog box, it will tell you how to do this.

stevenmorrison wrote:
Hello

ive had a query from the accountant in my work, now he has opened an
excel file which is saved on a network and has been working on it for a
couple of hours, now hears the problem, his assistant has also had the
file open and when the file is saved by either the accountant or
assistant, it is being over written,and data is being lost, now i have
told them to rename one of these files to assure all data is saved, but
i would like to know how to create an alert if an individual trys to
open a file which has already been opened on the network. :)

Thank You