You can connect to your Messenger account using Outlook Express by setting up a new Mail Account:
1. Start Outlook Express and got to Tools > Accounts
2. Click Add > Mail
3. Enter your name, and click Next

4. Enter your email address, and click Next

5. Enter the mail server addresses:
Incoming mail server - ems.esendex.net
Outgoing mail server - ems.esendex.net

Click Next
6. Enter your Esendex account details and password:
Account name - Your Esendex account reference and Esendex username in the format <Account Reference>\<Username>
e.g. EX0001234\person@mycompany.com
Password - The password you use to sign into the Esendex website

Click Next
7. Click Finish
8. Click Properties
9. Enter Esendex Messenger as the name for the account

10. Click the Server tab
11. Check My server requires authentication under Outgoing Mail Server
12. Click OK
13. Click Close
Once you have completed these steps you can send a text message from Outlook Express by:
1. Start Outlook Express and click the Create Mail button
2. Select the Esendex Messenger account from the From drop down list
(If you don't see a From drop down list, go to Step 3)

3. In the To box enter the recipients in the form <MobileNumber>@esendex.net for text SMS or <Mobilenumber>@voice.esendex.net for voice SMS. e.g. 07111122222@esendex.net
4. Type your text in the area below the Subject box.
5. Click Send
Next time you send and receive any text messages, received messages will be downloaded into your inbox. You can reply to them as you would a normal email. Outlook Express will automatically select the account that received the message.