Excel 2007 : Really Stuck

This has happened before - probably on an earlier version of the same spreadsheet. I try to open the spreadsheet and get the message "MS Office identified a potential security concern. Filepath c:\ (and identifies the file i am trying to open). Automatic update of links has been disabled. If you choose..." I then choose to "enable" content. The next message I get is "workbook contains one or more links that cannot be updated..." and I choose "continue" and then all I see is a totally blank spreadsheet (the actual spreadsheet is a large financial model) so it appears it never opens. then when I close excel it asks if I want to keep the updates to the file... BTW I have chosen to "edit" links and when the box comes up it shows no links to edit - completely blank... I am really stuck and i have hours in the spreadsheet! Please help.