Unwanted logon window

Hi to everybody, thank to anyone that could help me.

I do have a MacBookAIR 13" middle 2011,

1,7Ghz Intel Core i5,

4GB memory 1333 Mhz DDR3.

OS X Yosemite 10.10.3-

At switch on of my MAC, I do have a window that come up ( here attached ).

I believe that after a McAfee installation a logon script or whatever else, has been modified.

I would like to remove this logon window.

Could someone help me in identify what are the logon scripts and where are located ?

In my past I was using to modify autoexec.bat and config.sys, but it is a long while that I'm not using anymore a Windows system,

and I do not have intention to come back :-)

Thank you very much and

warm regards.

Sergio