XenApp 6.5 does not provide a binary upgrade path from XenApp 6.0. For some environments, the ability to create a new virtual machine image or clean installation XenApp 6.5 servers might not be possible.
The script performs what normally would be a long process of manually uninstalling XenApp 6.0 components in a select order, then installing XenApp 6.5. The following steps are performed:
1. Checks to see if XenApp 6.0 is installed or not, and if the XenApp 6.5 installer is available
2. Prompts for a password to silently run the install process after reboot.
Note: This is not stored by the script but is stored by the operating system in the Task Scheduler.
3. Uninstalls XenApp 6.0 components. By default these include the Online-Plugin, Management Consoles, and XenApp Application Delivery role.
Other components are included in the script and can be enabled for automatic removal.
4. Installs XenApp 6.5 and, by default, joins the server to the farm as a worker.
This can also be changed by editing the JOIN command parameters as outlined in the document.
5. Verifies the join is successful by checking to see if the IMA service is running.
The complete script and article can be found here