Generally, when giving instructions for users to back up their mail, I provide the Microsoft link originally provided by Roddy, but THAT'S NOT HOW I DO IT..Unfortunately, I've seen too many situations where e-mail folders were corrupted or e-mail programs died entirely...I don't mess with the .dbx files or any other files within the mail program itself. When I save my own personal mail, I do it differently. It may not be for everyone, but it works for me.
Here's how:
First, at the office, we use an "Exchange Server" which utilizes a server where all our mail is stored. There's really no need to back it up because our IT department takes care of that. Still, there are occasional bits of text or attachments that need to be saved and backed up. When I do find a specific mail message that I want saved in my personal documents, I simply copy and paste the text to a text file and save the text file in "My Documents" with an appropriate name. I then delete the message from my e-mail. Saving the file as a "message file" in Outlook Express or Outlook creates a "large" file while a text file of the same information is small.
On my home computers, the Outlook and Outlook Express folders are usually kept empty. Likewise, on my webmail folders. As before, if there is a special mail message that I want to save, I copy and paste the information to a text file, then save it to "My Documents". If there are any attachments, such as pictures or documents, I simply save the pictures/documents to the "My Documents/My Pictures" folder, then delete the message. I also create a small .csv file(comma separated value) as a backup to my "Contacts". The .csv file saves all my contact addresses in case the e-mail program dies. Instead of saving the .wab file which is a large file, the .csv if small and can be "exported/imported" easily in either Outlook Express or Outlook. Many other webmail types are able to use .csv files as well. To create a .csv file in Outlook Express, click on "File", choose "Export", choose "Address Book", then choose "Text File (comma separated values)", give the file a name you'll remember and follow the links to save the file to your "My Documents" folder. Microsoft Outlook 2002 is done in a similar manner by clicking on "File", choose "Import and Export", choose "Export to a File", choose "Comma Separated Value-Windows", then follow the prompts to save the small .csv file to your "My Document's folder.
There's an important advantage to all of this....When I burn backups/copies to a CD for storage, I only need to burn one folder. EVERYTHING of a personal nature is in the "My Documents" folder. Yes, I categorize various items in folders.."My Music", "My Videos", "My Mail", etc...but they're all in the "My Documents" folder and there's no hunting around the computer to find all the extra "stuff". It's all in one place.
Hope this helps.
Grif