Outlook and OWA Distribution List
Obtain addresses from Web Advisor, Excel, Email Message, Contact List, and other.
1.
In
Web Advisor, Highlight Class Roster
(starting at the top of the box).
Edit – Copy. Open Excel and Edit
– Paste Special
as Text. (Open) New Excel File and Edit
– Paste,
then, Highlight the e-mail address column,
use Edit – Copy.
Open New Excel File and Edit – Paste.
In Excel, Email Message and Contact List, use Edit – Copy.
2.
In Outlook, click on the File
menu, point to
New, and then click Distribution List.
In OWA, click on New mail message.
.
3. In Outlook, click Select Members.
In OWA, click on Address Book
4. In Outlook, in the Add to Distribution List – (members area), right-click, and then click Paste.
then 
In OWA, Move to Contacts.
CT has been asked, “Just how many recipients can be contained within a single Microsoft Outlook contact list? And the answer is….
There is no “magic number”: The contact list is based on number of characters, not size. And the size of any single contact list may be as large as 8,192 characters. How fast we reach that limit depends largely on how much information is carried along with the Email address. 40 users is a generally-accepted safe number, but you may be able to built a contact list with as many as 100 entries before Outlook complains.
For those of you just dying to put a little more Microsoft-ese into your life, you can access the full text of their answer by clicking here. Microsoft further recommends you break your contact list up into groups, then list those groups individually in the “To:” field of your message.