The only way I have found to do this is to use the built-in EXPORT functions.
In the main Windows Mail page, click FILE > EXPORT > MESSAGES, and then
select MICROSOFT WINDOWS MAIL.
When requested, browse to the desired folder to hold the backup files (e.g.
D:\Email_Backup), and then click NEXT.
Select the folder(s) to be backed-up, using shift and/or ctrl to select
multiple folders if necessary. Click NEXT and the FINISH once it is done.
The procedure is very similar for backing up contacts - simply export the
contacts to Vcard (vcf) files by clicking FILE > EXPORT > WINDOWS CONTACTS.
Importing back in is much the same as exporting - click FILE > IMPORT >
MESSAGES > MICROSOFT WINDOWS MAIL 7, and then select the same folder as above
(e.g. D:\Email_Backup). Click NEXT and select the folder(s) to be imported.
Again, it is much the same for the contacts.
Sadly, unlike Outlook, there does not yet appear to be a useful
'auto-backup' tool
Hope this helps!
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