Are you by chance using ClearspaceX instead of Clearspace? If so, you can try going to /clearspacex to see if that works.
If not, can you post any errors that might have shown up in your log files?
Also, were you using standalone before you upgraded?
no I'm using Cearspace.
Strange, we had Clearspace 1.1.1 Standalone running, after that I started 1.1.0 and then 1.2.0 again. Now it works; the upgrade console appeard.
Problem ocurred again upgrading from 1.2 to 1.3 (Clearspace Standalone NOT X)