Postbox can be used with Microsoft Exchange servers if they have IMAP support turned on. Here are some customizations to get the most out of using Postbox with your Exchange server
Change your Trash Folder
Exchange uses Deleted Items as the Trash folder.
On Windows select Options from the Tools menu, or on the Mac select Preferences from the Postbox menu.
Then click Accounts | <desired account> | Server Settings
[ ] Move it to this Folder [Trash]
Change Trash to Deleted Items.
Choose Copies & Folders if you want to change your Draft or Sent folders.
If it takes a long time to load a message
On Windows select Options from the Tools menu, or on the Mac select Preferences from the Postbox menu. Then click Accounts / < your server> / Server Settings
for the username field, if you entered your e-mail address including your domain name, try removing the domain name. i.e. instead of "firstname.lastname@example.org", try using just "scott."
If some of your Exchange folders aren't visible in the folder pane
Right-click on your inbox and select Subscribe... from the context menu. Make sure the missing folders are subscribed too.
Also, some Exchange servers work better with a certain setting. Go to Options | Preferences / Accounts / your Exchange account / Advanced Button.
Set this preference "show only subscribed folders" to OFF.
If you're having trouble configuring Postbox to search an LDAP directory with Microsoft Exchange, please make sure you the BIND DN attribute is filled in. Some users have found that adding their email address to this field allows LDAP lookups to function properly.