ePO 5.3 on a Windows 2008 SP2 64BIT server.
DLP 9.3 Patch 5
Internet Explorer 11
When I tried to log the DLP Host from McAfee EPO, the DLP Management Tools installed without issue.
But you get the message "Please reopen this page in order to see its content. If this message is still shown, contact your administrator".
I had reset IE Security to low, added the webpage to Trusted Sites, enabled ActiveX, reinstalled the DLP Management Tools from webapp, nothing works.
IE11 is technically not supported, though, as you see it can function. I would try reinstalling with User Access Control (UAC) disabled. There is a small note in the product guide or the release notes regarding UAC causing installation issues. If UAC is currently enabled it will require a system restart to disable.