Hi invizion,
this can happen if connection to all your pools is lost. Generally the message disappears when the pool is online again.
The miner also stops mining after a while if the pools stay down (and it cannot connect to any of your mining pool).

If you specified failover pools the miner should connect to the second (or third) pool.
Unfortunately there is a bug in the latest version and failover pools are not working...
We got this error now and it will be fixed in the next update.
Cheers