To follow up on the previous post I made about ILO scripting, this one runs through how you can change the password or add a user without having the login details to the ILO. I do thi al the time when I get new servers built in the field and while the local folks load the OS, they don't always remember to provide the username/password off the tag hanging off the server or they typo it, etc. This example also assumes that you have administrator level access to the actual server. You'll need hponcfg and the ILO driver loaded as discussed previously as well.
When you dump the ILO config, you'll be able to glean what users exist on the ILO from the info provided. In this example I'm just going to change the password for the admin user by using the following xml file. We'll set the password to "MyPassword".
<USER_INFO MODE="write">
<MOD_USER USER_LOGIN="admin">
The command to run is hponcfg /f iloconfig.xml where iloconfig.xml is the file holding the above text.