Can I upgrade my DCO 7.5 setup to latest ITA?

To upgrade the DCO 7.5 setup to the latest version of ITA, you must first update DCO to version 8.3.2:

1. Update your DCO 7.5 setup to version 8.3.2

1. Make sure you have a backup of your DCO 7.5 setup.

2. Perform a new clean installation of DCO 8.3.2.

3. Restore your configuration from the DCO 7.5 backup.

4. Create a backup this new 8.3.2 configuration.

2. Upgrade your DCO 8.3.2 setup to ITA 9.x
1. Perform a clean installation of the latest version of ITA 9.x. 
2. Restore your configuration from the backup of your DCO 8.3.2 setup.

See 

Installing IT Advisor (on-premise)

Installing ITA 9.1.1 and newer on Red Hat Enterprise Linux 8

Installing ITA on Red Hat Enterprise Linux 7 and 8