use gmail and thunderbird to overcome company mailbox quota issue

Jephe Wu  - http://linuxtechres.blogspot.com

Objective: due to small mailbox quota of company mailbox, so I'd like to use my gmail mailbox to store all my company emails also, whenever someone send me an email at gmail address or company email address, reply from the same address the message was sent to, from both browser and thunderbird.

We can import company ldap address book into google contacts and configure the local and google calendar in thunderbird.

Environment: gmail account, company users can set email forwarding by themselves, Thunderbird

Concepts:
I will configure my company email address jephe.wu@domain.com to forward to jephewu at gmail.com through whatever web interface provided by company. Then I can use web browser or thunderbird mail client to access both my gmail or company email.


Steps:
1. Enable IMAP access in your gmail account
You can login your gmail account from browser, go to account setting to enable IMAP access so that we can use thunderbird to access gmail later, search 'gmail imap' in google to access gmail help page at http://mail.google.com/support/bin/answer.py?hl=en&answer=75725  (Getting started with IMAP for Gmail)

2. configure your company mailbox forwarding function to forward jephe.wu@domain.com to jephewu at gmail.com.

3. Adding an external email account in gmail (setting - Accounts and Import) and set the company email as default, also, choose 'when receiving a message: Reply from the same address the message was sent to'. You can choose company email as default as most of time you will receive email from that address.

You can configure to send email through your company smtp server when replying those messages sent to your comany email address if your company smtp server has smtp auth enabled, otherwise, send it through google always.

4. Now when you use web browser to reply, it will reply from the same address the message was sent to.
You might need to import your company ldap address book into google contacts so that you can use it to compose email.  search 'gmail help' in google, go to gmail help page, search 'import csv files' to check how to import csv files to google contacts at http://mail.google.com/support/bin/answer.py?hl=en&answer=14024

5. Install Thunderbird, the latest version can automatically detect the gmail smtp/imap server name and configure it automatically. You will configure both your company address and gmail address.

6. In order to reply from the same the message was sent to in thunderbird, you can search 'thunderbird multiple accounts' in google, check the page at http://www.askdavetaylor.com/how_do_i_create_multiple_accounts_in_mozilla_thunderbird.html

7. You can now configure ldap address book in thunderbird.

8. You can also install lightning  - a integrated calendar for thunderbird 
You can also install 'provider for google calendar' to allow bidirectional access to Google calendar, please check howto at http://bfish.xaedalus.net/2007/04/stay-in-sync-with-gcal-and-thunderbird/

FAQ.

a. testing your company smtp server smtp auth through command line (assuming your username and password for smtp auth is jephe.wu and password)
$ echo -n "jephe.wu" | openssl enc -base64
amVwaGUud3U=
$ echo -n "password" | openssl enc -base64
cGFzc3dvcmQ=
telnet mailserver 25/587
ehlo abc
auth login
334 VXNlcm5hbWU6
amVwaGUud3U=
334 UGFzc3dvcmQ6
cGFzc3dvcmQ=