Please review the below KB article (check for the missing DLLs) and see if it applies. If it does not, please open a Service Request with McAfee Support for further investigation.
I've resolved this by uninstalling ENS and sometimes the Agent as well with the 2.3 version of the removal tool. Another problem I've seen along with this is you cannot open file explorer to get to the removal tool once you copied it over. Use IE or FF to browse to the folder containing the removal tool, then run it in graphical mode. Make sure you reboot the system after uninstalling, then install from the stand-alone installer or ePO.
Download the new ePolicy Orchestrator (ePO) Support Center Extension which simplifies ePO management and provides support resources directly in the console. Learn more about ePO Support Center