I'm running windows 7 64 bit version 6.1.7600 Build 7600. I downloaded an Excel file from a trusted site and I can't open it. when I try to open it directly from the website I get messages like it's read-only, or already open, name and path may be invalid, or may no longer exist. Or, I can save it, and then when I try to open it I'm told that it's encrypted or password protected, and then I'm advised to open it in the program that created it and remove password etc. When I save it to the desktop it saves with the appropriate name and icon. I can open the file from my ancient computer at work running XP and microsoft office 2003. However, when I email the file from work to home, I still can't open it. I'm running Bitdefender anti-virus, and my email provider is Yahoo. I tried disabling my antivirus but that didn't help.