What does an open envelope with an "i" on it mean?

[mick@sca]

In my sent items I have noticed some of the items have an open envelope with
an "i" on the envelope. this is in the column where read, forwarded, or other
icons appear.
What does this signify?

 

[Milly Staples [MVP - Outlook]]

http://www.howto-outlook.com/howto/icons.htm

--
Milly Staples [MVP - Outlook]

Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.

After furious head scratching, mick@sca asked:

| In my sent items I have noticed some of the items have an open
| envelope with an "i" on the envelope. this is in the column where
| read, forwarded, or other icons appear.
| What does this signify?