UPDATE: Found solution - as per -US/kb/use-java-plugin-to-view-interactive-content it can be fixed by removing pluginreg.dat in the profile folder (instructions for locating this can be found at the site).
UPDATE: Found solution - as per -US/kb/use-java-plugin-to-view-interactive-content it can be fixed by removing pluginreg.dat in the profile folder (instructions for locating this can be found at the site).