GNUradio and Windows 7 still need help

I have been running a relatively simple program on my Linux computer but
when trying to run it on the Windows computer I get the following error:
:Invalid argument
No such file or directory
:Invalid argument

The program consists of a File Source going to a Throttle going to both
a WX GUI FFT Sink and a WX GUI Waterfall Sink. When I run the program
both the Waterfall and FFT positions come up but only the Waterfall
actually appears but with nothing happening. If I disable the Waterfall
Sink then the FFT grid comes up but with nothing happening. And of
course the above error message comes up in each case.

Any help would be appreciated.

Many thanks,