Hi Diana;
It looks like host name issue.
Your host name is not getting resolved. Try to run any sicf service from SICF tcode. I think for all the services you will be gettting the same erro.
Please maintain it your hosts file in the system.
<hostname.domainname> : <IP address>
or try to access directly by IP address.
Also for odata testing you can use gateway client for testing.
but eventually you need to maintain the hostname in the hosts file in the system to run the launchpad and launchpad designer.
If all the above doesnot solve the issue, please check any console errors in the browser's developer tool and any errors in the netweaver error logs tcode (/IWFND/ERROR_LOG).
Regards,
Sarbjeet Singh