You posted to a forum for Live Mesh - www.mesh.com - you should have posted here:
http://social.answers.microsoft.com/Forums/en-US/group/mymobilephone
However, assuming that you are talking about Outlook on the PC and Outlook on the phone, the default is to sync the Inbox. If your email is using an Exchange account, you can configure additional folders to sync, if desired. That's done in Options/Tools/Manage
folders for the account on the phone.
If you are using POP account, that's not an option.
If you are synchronizing with a Hotmail account, it is also Options/Tools/Manage folders on the phone.
Note that the messages in the phone's folders will be limited to the days specified to retain on the phone.
-steve
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