Currently EIT has been blocking the most recent MAC OS upgrade. This is because the OS is 64-Bit only. If you have software that was installed as 32-Bit, it will need to be reinstalled as 64-Bit. Once this OS is allowed, you are unable to roll the update back. Please check an make sure your software is installed as 64-Bit or make sure you still have access to all your software installs so you can upgrade. If you have questions or need assistance in making this determination, please contact the hotline prior to upgrading.