Read only dialong box doesnt appear
 

I have several users who have exel spreadsheets on a shared network drive.
THey are claiming that when one of them has a file open and the others try to
access it, they do not get the "file in use" dialog box.

I have tried this with the other sysadmins and we all get the file in use
etc etc

has anyone seen this/or got any suggestions?

thanks

Steve