How to make restoration of corrupted excel 2007 file?

Hi there,

When I open an excel file the following error message is displayed: “The file may be corrupted, located on a server that is not responding, or read only”. Since this happened whenever I open any excel file, the above error message is again displayed, I must also mention that I am sure my files are not read-only and the files are stored on my hard disk and I use VM ware and my OS is windows server!

How can I solve this problem?