The headline of this blog post might sound simple, but it can be extremely annoying to get the Client Integration Plug-in running to import virtual appliances. No matter if you use IE, Chrome or Firefox you can find yourself surrounded with error messages and information that your you Client plugin needs to be installed (despite the fact, that you just installed it some minutes ago and restarted your browser). A very common message is also “The VMware Client Integration Plugin has updated its SSL certificate in Firefox. Please Restart Firefox.” The reason is the required NPAPI support, that most browser don´t support anymore. It even gets worse, as latest browser versions don´t allow to re-enable the NPAPI support. Most of the errors are fixed in vSphere 6.5 but still existing in all versions before. As many people still run vSphere 6.0 I want to guide you through the Firefox installation, to make sure the Client Integration Plug-In is working.