In VMWare, there is a "hardware version" set on each VM that determines some attributes of the VM. For PAM, the default Hardware Version is 7.
Here is an example of where to find the version:
What VMWare hardware versions does PAM support? How will changing the hardware version effect PAM?
PAM running on VMWare
PAM has only been officially certified to work with VMWare Hardware Version 7. Changing to any other Hardware version is unsupported and may cause unexpected results.
Once upgraded, there is no way to "downgrade" the hardware version. The only option is to delete the current VM and create a new one using the correct Hardware Version.
Since this has never been officially tested there could be any number of issues with changing this option. One specific example of an issue that was seen is that after upgrading the Hardware Version to 13, the appliance appeared to boot correctly (the blue console screen appeared) but when trying to access PAM it failed with the following messages and PINGs didn't reach the device: From a Browser: "Unable to connect" From PAM Client: "Checking for update failed. Reason: Connection refused: connect"