Comment 38 for bug 805379

Version zipped up from GIT works here. Fedora 15, 32 bit, Thunderbird 5.0. Using Exchange 2007 hosted with (nasty_hosted_exchange_provider). For those wanting a recipe:

git clone git://gitorious.org/lightning-exchange-provider/lightning-exchange-provider.git lightning-exchange-provider
cd lightning-exchange-provider
zip -r ../lightning-exchange-provider.xpi *

Then add by clicking on the "Install Add-On From A File" in the Add-ons Manager and point it at the lightning-exchange-provider.xpi file. It'll whine that it's unsigned, but so it goes. Then it'll prompt you to restart. Do so.

Then go into calendars, right-click in the Calendar area to add your calendar, put in your usual
https://DOMAIN\<email address hidden>/EWS/Exchange.asmx as the path, and when it prompts you for your password add it in. Voila. All works.

Note: If your company is using a hosted Exchange service you'll need to go into their web services dashboard and get your "real" Exchange user name and Windows domain. It's usually something like <email address hidden> with a random Windows domain name of their choice. Just one of the joys of outsourcing, sigh...