The ePO 3.6.1 console is not supported on Windows Vista or Windows 7. Ref KB51569:
We have not updated that KB yet to reflect that the EPO 3.6.1 console does not support Windows 7 but it is not supported in Windows Vista so you can infer that it will also not be supported in Windows 7. As EPO 3.6.1 is EOL at the end of this month and no further patches are in development for EPO 3.6.1 it is highly unlikely that support for Windows Vista or Windows 7 (or any new operating system) will ever be introduced for the EPO 3.6.1 console.
EPO 4.X's console is browser based so the OS is irelevent you just have to use a supported browser. See the same KB for supported browsers for EPO 4.X.
The following statement will be added to that KB shortly:
Note: Support of the ePO 3.6.1 console on any new OS other than what is listed will not be provided. ePO 3.6.1 is End-of-Life on Dec. 31, 2009.