To have Windows Live Mail save ... copies of sent messages on the IMAP server (rather than on your PC), set the following options:
Check the box marked "Store special folders on IMAP server". (Otherwise, drafts, deleted, and sent messages will be stored on your local hard disk -- which is called "Storage Folders" by Windows Live Mail). Enter Sent for the "Sent Items Path". Enter Drafts for the "Drafts path". Enter Trash for the "Deleted Items path". You can leave the "Junk path" set to whatever folder name you desire.
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