It is important to verify the uploaded files cxu.xmt and cxufree.xmt on the mainframe to ensure they do not contain anything else than what is described on this site.

Please follow this description in TSO/ISPF:

1. Execute command: TSO %ISHELL
2. Choose Tools in the tools bar at the top of the panel
3. Choose 3. Run program(EX)...
4. Execute command: sha256 "//CXU.XMT"
   The result should be the value: e5da3ebe51effbdbb0ed11e1496d3e5513eb47ef1a7d0c23a6f00854c5a5d119
5. If you also have downloaded the CXU source then execute command: sha256 "//CXUFREE.XMT"
   The result should be the value: eee8fc5afcebda1b044dac37b6b3c5bbbda37dc8638e39141d26219a7ec22fdc

Please note you have to use F11 (RIGHT) to see the complete value returned by the sha256 command.

The above commands are standard on any TSO/ISPF installation.