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$ pico .forward
username@columbia.edu
$ rm .forward
You should begin to receive e-mail in your Barnard inbox again.
Make sure NOT to set both accounts forwarding to each other at the same time, or mail sent to either account will bounce back and forth until it is returned to sender.
An email signature is a line (or a few lines) that is automatically appended to the bottom of all of your outgoing emails. You can use this to include contact information, just your name, or a message (like "my email address is changing!").
To setup a signature using Pine, login then type "S" for Setup. Once your are in the SETUP menu, type "S" for Signature. Now you can type whatever you want your signature to be. When you're done, hit ctrl and "X" at the same time then type "Y" to save your changes.
To setup a signature using Webmail, login then choose "Options" from the choices at the top of the page. Now choose "Personal Information" and you cane change/enter a signature on this page. Remember to "Submit" your changes to save them.
To setup a signature for your Gmail account, login and choose "Settings" on the top-right of the window. Under the "General" tab you can setup a signature.
If you use an email client, you can have multiple signatures (personal, professional etc.), think of the possibilities!