Thunderbird client is far better than Outlook, however, it lacks the Calendar support like Outlook until now. There have been some great improvements and one of them is the ability to sync any calendar, including Outlook to Thunderbird via Lightening Addon.
1. Install the Lightening Calendar Add-on via Tools, Addons
2. Download and add the file Addon for web-mail-1-4-3.xpi
3. Download Davmail Download davmail-4.1.0-2042-setup.exe (9.0 MB) via http://sourceforge.net/projects/davmail/files/
Davmail is a server on your desktop that talks to your Exchange server via webmail and is able to populate the Lightening with calendar information. So, you will be connecting to the calendar locally to Davmail, which in turn will be connecting to your Exchange server using your webmail login.
4. Download and install latest Java on your computer, Davmail requires it.
Once Dave mail is installed, fire up Davmail and make the changes to the configuration to suit your needs.
Notice OWA URL: make it your own https://webmail.yourcompany.com/owa or https://webmail.yourcompany.com/exchange. Whatever you see on your browser when connecting via webmail.
Ports are important. You will have to know how you connect to POP or IMAP and use appropriate port numbers.
Caldav and LDAP leave as default.
Click Save
You should connect to your server without any problems if you have the correct port numbers.
Once Davmail is running you can then go to Thunderbird Lightening and create a new Calendar.
1. Choose Network Calendar
2. Choose CalDav
3. Location type in the following
http://localhost:1080/users/mail@company.com/calendar
notice you are connecting to Davmail, not your Exchange server. Notice the port number of 1080 which is the same on Davmail and notice /users/ this is important leave it there.
4. Change the mail@company.com to your email address such as salma@mail.com. Notice /calendar leave it as is. You should end up with
http://localhost:1080/users/salma@mail.com/calendar
5.Click on Cache and pick a good color. Each entry will be of that color!
Done!
Sweet to have it all working.!