launch lounge

There are already a hand full of tutorials out there that describe on how to change the login background picture, but I was fighting for some time to get it to work. Just wanted to share my findings so that you don’t have to get through these issues as well.

This hack was done on the Snow Leopard release, but should also work on Leopard. Some tutorials describe on how to replace the /System/Library/CoreServices/DefaultDesktop.jpg”, I personally wouldn’t do that since this image is part of the core OS. To do it the “clean way” (I am sure we can debate about that) I think it is better to change the plist properties file which contains the pointer to the picture.

It is important doe to make sure that the picture has the following format: JPG / 2560 x 1600 / 72 dpi. You may change this settings with the preview app and save your picture accordingly.

Also make sure that the picture is accessible by all the users, so for me the best place to put the background was /Users/Shared. This can be customized based on your needs, but make sure that everyone has at least read access.

To link to the new background picture you have to update the DesktopPicture property in the com.apple.loginwindow.plist file. To do this use the following command in your terminal window.

sudo defaults write /Library/Preferences/com.apple.loginwindow DesktopPicture "full path and name to your jpg file“

Replace the “full path and name to your jpg file” bit with the full path and filename of the image you’d like to use (e.g. /Users/Shared/LoginBackground.jpg).

Log out and you should see your new login window background picture. If you see a plain blue background, make sure that the picture meets the above mentioned requirements and that the path in the properties file is correct.

To reset to the original picture just use the following command.

sudo defaults write /Library/Preferences/com.apple.loginwindow DesktopPicture "/System/Library/CoreServices/DefaultDesktop.jpg"

Enjoy and let me know if you had success or issues.

This entry was posted on Friday, August 28th, 2009 at 8:05 pm and is filed under OS X. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.