How to modify the Win7 file association and opening method?

Because the work needs to analyze the source of a message, etc., because I am used to using Office Outook to view the mail attribute information, and the current system default mail program is Windows Live Mail, so use the "open method" specified by Office Outlook opens the message, but when the open mode is specified, it is inadvertent, and the result of the check is not removed. "Always use the selected program to open this file".

And after this operation is executed, Office Outlook does not open the correct mail file (.eml type) correctly. Now it can only restore the previous state first. According to the experience of using Windows XP in the past, the folder option In rdquo; you can set the file key and open mode, but it is confused under Windows 7, and found it for a long time!
Because it is the reason of RC version, it is difficult to search for relevant information in the help system. At least a few keywords can't be searched for related help. But I can be sure that the system will have a place to set up. This reminds me of the control panel —— system configuration center, after trying hard to find the location.

Open the control panel. By default, the control panel is arranged in categories, so as shown in the figure below, we need to click on “Program” to find the default program settings. Here we can change Specifies how the type file is opened and the default program settings.

Of course, under the category list arrangement, we may not be able to intuitively let us know the specific information of each setting function. I personally recommend switching the viewing mode to "large icon", so that I can be clear Know the name of each setting function.
Click "“Set default program", we can see the default program currently registered in the system in the program list box on the left side of the figure below, select Windows Live Mail, and click on the right side of the program to select the default of this program Value ”, then check the extension of the type of “.eml” in “Setup Program Association" and click OK to complete the setup.
Of course, we can also specify the opening method for a specific file type by clicking on the file type or protocol associated with the program in the default program settings panel.