Installing IBM i 7.5 over IBM i 7.3

If you are installing IBM® i 7.5 over IBM i 7.3, you should also read the IBM i Memo to Users for IBM i 7.4. It contains incompatibility-related information about the new functions and enhancements incorporated in IBM i 7.4.

You can also view the IBM i 7.4 IBM i Memo to Users in IBM Docs under the IBM i 7.4 release :

https://www.ibm.com/docs/en/i/7.4?topic=information-memo-users