When you archive a Mail message folder, Microsoft Outlook determines the
message age from the Sent date/time, the Received date/time, or from the
message's Modified date/time, whichever is later.
The following actions will change the message's modified date/time:
- Forwarding
- Replying
- Replying to All
- Editing and Saving
- Moving or Copying
Copying or moving the message to another message folder does not always
change the modification date/time; if the destination folder is a Personal
Folders file (.pst), the modification date/time does not change. If the
destination folder is an Exchange Server Mailbox or an Offline Folders file
(.ost), the modification date/time does change.
To determine the latest modification date/time of a Mail message, follow
these steps:
- On the View menu, point to Current View and click Customize Current
View.
- Click Fields and in the "Select available fields from" list, click "All
Mail fields."
- Under Available Fields, click Modified, and then click Add
to place the Modified field in the "Show these fields in this order"
list.
- Click Move Up or Move Down to position the Modified field and click
OK and OK.
The modified date/time for each message now appears in the Messages view.