The .eml files are attached to emails. But there is no a program to open the file in Windows 7. How can I open the .eml file?
First you need to install a email client program in Windows 7, such as Windows Live Mail. By default Win7 don't have a email client program installed.
Download the Windows Live here. Once have installed it, you need to made it as the default program first.
If you use Windows Outlook, try a simple way:
Open the Outlook program --> select the Drafts tab --> drag your .eml files into the Drafts area --> now you can view the .eml file.