Upgraded vCenter to v6.7 and RP4VM to 5.2.2.1 and plugin in flex client missing

Several of our datacenter still running vSphere 6.0u3/RP4VM 4.4.1.1 and we are trying to upgrade them all to v6.7 and RP4VM 5.2.2.1. RP4VM process was upgraded successfully and made sure everything was working prior to upgrading vSphere. Once the vCenter was upgraded to v6.7d which is in the supported version matrix the plugin will not load. When access the web client it will pop bunch of plugin loading error messages and the client is not useable. If accessing thru HTML5 everything works but there is no RP4VM plugin which is not supported. 

Errors:

Internal error occurred: Error #1009. Reloading the client is recommended, so as to clear any problem left by this error. Reloading does not help.

Invalid extension-point: sphere.core.tasks.recentTaskViews

Once click pass all the error, the client will be missing all the buttons, icons on the left, right and bottom pane. Click thru any icon will leave session clocking and eventually timeout.

Any one know how to resolve this plugin issue???