A quick way to check that the database is running, is to point a browser to the http port. The following example URLs will show the System Manager for the default, and the demo Virtuoso databases:

http://example.com
http://example.com:8890

Install failure

Check the .log file in your Virtuoso installation db location, for ex:

        C:\Program Files\OpenLink Software\Virtuoso 7.2\db\virtuoso.log

which is for the database and log files etc. in order to review the installed files binaries and databases (defaults) for issues if install fails.

.lck existance

Check .log in case of .lck issue

Delete the .lck file and repeat the steps from above.

.trx incompatiblity issue

Check .log in case of .trx incompatiblity issue

oplmgr issue

See Troubleshooting License Problems