Create Folders and File your Mail in Outlook Express
In Outlook Express, right click on "Local Folders" to display a drop down menu.

NOTE: Make sure that your cursor is on "Local Folder" before you right click - otherwise the new folder that you are about to create will be displayed under the folder that you clicked on.
Select "New Folder" from the menu and left click. Type the name you wish to call your folder and click OK.
The newly created folder will appear in your Folder List. To file your email messages in this folder - left click on the message and drag the message across and drop it on the folder (Folder needs to be highlighted before you release the mouse button)
The screenshot above shows the email mail message from Microsoft being moved from the "Inbox" to the "Test Folder" that was created.