If you set up Notes at the office, you probably do not have all of the connection settings required to access the Notes/Domino server from outside the office network.
1. Find out what the full hierarchical sever name is, often in a format such as ServerName/Company or Server/Location/Company.
2. Find the public IP address or hostname of your server, this may be in a format such as 209.129.18.79. Or if you access mail from a web browser, you can probably use that url address, such as mail.domain.com.
3. Open your personal address book and click on the Advanced link at the bottom of the left navigator.
4. Click on Connections in the left navigator.
5. You can have any number of connection documents, one for every server you connect to. I'm guessing you will only have one. Open this connection document in edit mode. On the Basics Tab, add the correct hierarchical sever name in the Server Name field. On the Advanced Tab, enter the IP address or hostname in the Destination server address field. Save and Close.
6. If this does not give you immediate access to your server, hit Ctrl+O to access the Open Database dialog, then enter the IP or hostname in the "Look in" field, and hit the enter key. This will simply assist the Notes in locating the Server. If you successfully return a list of database, you can close the dialog box, then open your email.