Rated 5 out of 5 stars

First thing first, I used MozBackup to backup Email and Address Book ONLY in order to keep important emails and contacts.
Make sure I have got a backup of my Profile folder as follows:
"C:\Users\<Windows user name>\AppData\Roaming\Thunderbird\Profiles\<Profile name>\"
Uninstall older TB and completely remove my Profile folder.
Install new TB5.0 and then try to open it up (failed the first time).
Now make sure TB5.0 is closed.
Go into the new Profile folder and locate profile.ini and make sure the following lines exist:
"StartWithLastProfile=0"
Restore the backup from MozBackup.
Start TB5.0 all over again and install following add-ons:
Lightning 1.0b4,
Provider for Google Calendar 0.8,
Provider for Microsoft Exchange 0.16 [Manual install]
(https://addons.mozilla.org/en-us/thunderbird/addon/195279/versions/0.16)
Follow the guide on http://gitorious.org/lightning-exchange-provider/pages/Home
to add new Exchange Calendar without auto discovery using the following URL in settings:
https://$ADdomain\$login@$exchangeserver/EWS/Exchange.asmx

Done with Exchange Calendar 2007!

This review is for a previous version of the add-on (0.15).  This user has 2 previous reviews of this add-on.