IO error.. Pls help me.

[NexuSnajper]

Hello, Please help me, i have problem.
Whem i push Start mining, program tell me:
'no response to getwork, using as stratum'
'Failed to subscribe'
'IO errors - 1, tolerance2'

Please what happend?
What i must do? I restart my computer two times but no changes.
Help..
Thanks.