My server is running Windows 2003.It is running domain.It shares some folders and Excel files.Serveral computers join the domain and link to server's share folders and Excel files.Most of them have no problem but only 2 of them.Normally, if one computer opens the server's share Excel file, other computers will have a read-only status when opening that shared Excel file.1a. There is a Windows 7 computer. When it opens the server's shared Excel file, other computers can still open that shared Excel file normally, i.e. no read-only status.1b. When that Windows 7 computer saves that server's shared Excel file, it can't save that shared Excel file when other computers are opening that shared Excel file at the same time.1c. When that Windows 7 computer opens serveral server's shared Excel files, it can't save and then it will automatically close all the excel files.Is this the problems of Windows 2003 and Windows 7? or other problems?2a. There is another Windows XP computer. When it opens the server's shared Excel file, it will break down the connection to the internet and also to the server. If I type "ipconfig /renew" at command prompt, it can't get the IP.2b. But after rebooting, that computer will return to normal. It can go to the internet and go to the server's share folder. It can also gett the IP. But if I open the server's shared Excel file, it will break down the connection to the internet and also to the server again.2c. I check that there is no virus in the computer.Does anyone have ideas?Thank you very much.1 person needs an answerI do too