Using Thunderbird as Client for Gmail

in your gmail account enable IMAP (that's in settings→forwarding and POP/IMAP)
configure a new imap account in thunderbird with
1. imap server: imap.gmail.com (use ssl, port 993)
2. smtp server: smtp.gmail.com (use ssl, port 465)
3. username: prefix before @gmail.com or if you use google apps for businesses your whole email address

install lightning addon for calendar access
create a new calendar, choose on the network and CalDAV. in the location field enter:
```
https://www.google.com/calendar/dav/<yourFullEmailAddress>/events
```
if someone else shared his/her calendar with you, you can add another calendar like above but with this type of url:
```
https://www.google.com/calendar/dav/<theOtherPersonsEmailAddress>/events
```
don't ask me how it knows which user and password to use to login, it just seems to work somehow ..

install Google Contacts addon
if it does not automatically detect your gmail account from the email settings add it manually:
1. in the addons manager find this addon and click on Preferences
2. add your account(s) and click ok
you may need to restart thunderbird to see the new addressbook
if you have access to other people's addressbooks i.e. through google apps for businesses, it will automatically show your and all shared addressbooks you have access to once you set up your account.

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