Letterbox which is the popular plugin for Mail.app for Mac OS X user is now broken. The Mac OS X 10.6.5 update broke this plugin. This plugin for Mail.app provides a wide screen three pane view in Mail. Good news is that now you can fix letterbox mail plugin in Mac OS X 10.6.5. Below are the instructions using which you can fix the plugin to work in 10.6.5.
STEP 1. From the Finder, click Command+Shift+G and enter ~/Library/Mail/ then hit Go.
STEP 2. Open Bundles (Disabled) rather than Bundles.
NOTE : If you have already opened Mail, the plugin is disabled otherwise it will be in Bundles if you haven’t opened Mail yet
STEP 3. Now right click on Letterbox.mailbundle then select “Show Package Contents”
STEP 4. Inside the Letterbox.mailbundle contents open the “Contents” folder
STEP 5. Open Info.plist using a text editor (You can use TextEdit but don’t use any Word)
STEP 6. Now scroll to the bottom of the Info.plist file and look for “SupportedPluginCompatibilityUUIDs”. It is surrounded by key tags and below that will be a bunch of hex strings surrounded by string tags.
STEP 7. Now add the following two strings to the bottom of the list (inside the array tags):
The newly inserted strings should look like the below image,
STEP 8. Now save these changes to the Info.plist file.
STEP 9. Now go back to the Mac OS X desktop and again hit Command+Shift+G, then enter ~/Library/Mail/
STEP 10. You’ll see these two folders again: Bundles (Disabled) and Bundles, now you should move the Letterbox.mailbundle plugin from the (Disabled) folder to the Bundles folder just by dragging the file from one folder window to the other.
STEP 11. Now relaunch Mail.app
When you open the Mail app again, your Letterbox plugin will be restored. In this way you can fix letterbox mail plugin in Mac OS X 10.6.5. Stay tuned with us for more updates.