Won't let me play back

When ever I try to play back a certain song it says “Error while trying to open sound device. Please check output device settings and project sample rate” How exactly do I check this?
I’m pretty sure my computer is Windows 7.
Any help would be greatly appriciated

Please try the steps in this Frequently Asked Question:
http://manual.audacityteam.org/o/man/faq_errors.html#sound_device .

Also check the input devices while you are there if you are intending to record anything.