ProTools 11 could not initialize Focusrite USB 2.0 Audio Driver

[grohee]

Brand new ProTools 11 with Focusrite Scarlett 18i8 USB Interface will not be initialized using Protools. When I hit 'play' or 'record' on Transport the following error message in Protools: Pro Tools could not initialize the Focusrite USB 2.0 Audio Driver. Please make sure that the device has been configured correctly.

Anyone... very frustrated now so searching for any suggestions?

Background: Using Windows 7 Pro 64 Bit OS on laptop core I7 with 8MB RAM.

Things I tried:

-Scarlett 18i8 MixControl works with meaning I can insert audio from phone, or laptop and hear it from headphone input on USB Audio Interface, and also playing instrument using guitar... so this seems to mean the PC recognizes the USB interface. Set as input & record on PC Scarlett as default. Also ITunes plays through Scarlett fine.

-Start up Protools 11 (also tried 11.2.2) and it recognizes Scarlett 18i8 as only USB interface so in I/O Setup window the A - shows Focusrite USB20AudioDriver for both Input and Output. BUT - try to hit Play and I get the unable to initialize USB Audio Interface. Essentially, I can't get this thing to play or hear music tracks (not even the demo, or prior Protool tracks from other recording studios I've used).

any ideas... other than boat anchor ? Or have I missed a basic setting as I'm very new to Protools. Also used by buddy at Sam Ash to review, but hours later, still not working.

Thank you!