Hi,
I realised this is a common problem that Sentinel user came across. However, most posts are too old and the most of the links are dead.
The error message I got is:
From http://localhost:1947/_int_/diag.html I can see the Run-time Installer and Run-time Package version are 8.13. Please let me know what other information I can provide to debug this problem.Sentinel LDK Protection System: Sentinel License Manager version too old (H0042)