A colleague just had the same problem.
The cause of the error was, that another process already listening at port 9001 on the computer, which the HSQL database uses by default for connecting.
With the cmd command 'netstat -ao | find "9001"' or as admin 'netstat -aob | find "9001"' the running process can be displayed. In our case it was the PID 4 [System].
With the command 'netsh http show servicestate' we found the responsible program.
The entry which we found was:
Registered URLs:
HTTP: // +: 9001 / IGCC / SERVICE /
After the service 'Intel Graphic Command Center' (IGCC) has been deactivated in the task manager, the database viewer starts normally.