Error Explanation

Hello. I'm using hashcat 3.00 beta. When I use the following command, 

"hashcat -m 2500 -a 3 C:\Users\Zakshc\Documents\capture.hccap ?d?d?d?d?d?d?d?d?d?d"

I get the following error,

"Initializing device kernels and memory...
ERROR: clCreateContext() : -2 : CL_UNKNOWN_ERROR"

Would someone mind explaining what this error means and how I can fix it?

Thanks,
H