I recently ran into a problem on two identical hosts where a plug-in that I am developing appeared as "Disabled" in the plug-in manager. Prior to this day, the plug-in has been working without any issues. When the user attempted to "Enable" the plug-in, it had no effect. The plug-in just stayed as "disabled."

I tried a number of different tweaks to get this working and I eventually found the file, C:\Documents and Settings\Administrator\Local Settings\Application Data\VMware\vpx\PluginCache\cache.xml. Once I deleted this file and re-loaded vSphere Client, the plug-in was enabled again. Upon exit of vSphere Client, this file was recreated again.

Can anyone describe the use of this file? Any insight into why it might force my plug-in to be disabled?