BSA 8.3.03 does not support RHEL 7 so you are not able to browse and perform any operation on RHEL 7 server but can do on RHEL 5/6 servers. You can refer compatibility matrix for same.
Ashish's answer is correct, we do not support RHEL 7 in the BSA release you are currently using.
Here is the link to the compatibility matrix he mentioned. BMC Product Availability and Compatibility Utility
Thanks Ashish/Alan for the info !
I will check with customer if they can upgrade BSA 8.3 to newer version that supports RHEL 7.