Get GD fully working version
Your Drupal 6 Status report page returns the following error
GD Image Rotation Low Quality / Poor Performance
The installed version of PHP GD does not support ...
Here is the steps for Ubuntu Server 8.04.x LTS, PHP5, Drupal 5.x or 6.x. It has also been found to work with Ubuntu Server 9.04. It will install a GD pre-compiled fully working version. It is a complete bundled (forked) GD libraries.
If not already done type in the following command in your TERMINAL to remove your current GD package and its configurations.
sudo apt-get --purge remove php5-gd
Add 2 lines at the end of your file /etc/apt/sources.list
deb http://packages.dotdeb.org stable all deb-src http://packages.dotdeb.org stable all
Type in the following command in your TERMINAL to update your current apt-get list
Type in the following command in your TERMINAL to install the working GD package.
apt-get install php5-gd
Wait. When asked 'Do you want to continue' press Y key. Then press RETURN key.
When asked 'Install these packages without verification' press Y key. Then press RETURN key.
This is optional but you might want to make a backup of your php.ini file. Because it might be modify during the following steps. The php.ini file is located under /etc/php5/apache2/php.ini
Important note: If you have customized your php.ini file all your edits will be erase during the following steps. You will have to edit your php.ini file later. If you have not customized your php.ini file ignore this note and just go to next step.
When asked 'What would you like to do about php.ini?' select the 'MAINTAINER'S VERSION'. Press Y key. Then press ENTER key.
Wait. If successful TERMINAL will return 'ldconfig deferred processing now taking place'.
Type in the following command in your TERMINAL to restart your Apache.
Go to http://your-domain-name-here.com/admin/reports/status to test it. GD line should have a green checkmark.
If it doesn't work restart your whole Ubuntu server. Wait a few minutes. Then test again.