Passwords and Automatic Sign Ins

Last week I picked up a new machine running Win 8.1.

When I turned it on, NO password was required - it booted right to my desktop.

Sometime over the weekend, something "strange" occurred - when I start the machine, I'm presented with a screen as follows:

          Terry

          *** Email address is removed for privacy ***

          Password

I entered several passwords which I know to be valid from other applications, BUT the ONLY password it accepts is my Hotmail Password.

I have no problems with a password for security reasons, but this combination creates some "privacy" issues.

When I get to my desktop and open Internet Explorer and "click" on the Outlook.com tile, Hotmail opens directly into my Inbox.  This is totally unacceptable for a family PC - unless I turn off the machine , anyone can read my Hotmails.

So, to my questions:

How do I stop this - I've followed all the instructions in the Win 8 help file - swipe up from the bottom right corner, select the "Search" icon, type in sign, and click on Sign In Options.  I've checked the "No Password option, and the screen clearly says "No password required for this computer", yet, when I reboot, the process repeats.

Is this a Windows software issue?, a hardware issue? or an Outlook.com Issue?  I hate the idea of re-installing my OS.

Any and all help appreciated.

Thanks,

Terry