Timeline Indicator Does Not Move ..New to PT11. Help!

I have just loaded up PT11 for the first time but nothing happens when I press play ..the timeline indicator doesn't move. I am using a newly built PC running Windows 8.1 along with using a Focusrite Scarlett 214 interface. As far as I know everything is set up right. I have looked through documentation and help (both are pretty hopeless at trouble shooting) as well as just trying to figure it out by playing around. Obviously I have selected the 2i4 as the default sound interface in Windows as well as cheking the I/O settings, etc within PT11 (though I have to say the options within PT11 are very limited). Pro Tools is recognizing the 2i4. Regardless of this the timeline indicator should not in my experience of sequencers be affected by any of the above ..it should just work. Never had such a problem before. Can anybody help?



Thanks.