You are missing "-epsw x"
Nanopool has a config generator for the Claymore miner, just click on "Quick Start" and it will create one for you. This is what I get and it works, just put in your details into the grenerator.
Thanks

EDIT
Found in nanopool site
However in nanoool site the example is:
setx GPU_FORCE_64BIT_PTR 0
setx GPU_MAX_HEAP_SIZE 100
setx GPU_USE_SYNC_OBJECTS 1
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_SINGLE_ALLOC_PERCENT 100
EthDcrMiner64.exe -epool eth-eu1.nanopool.org:9999 -ewal YOUR_ETH_ADDRESS/YOUR_WORKER_NAME/YOUR_EMAIL -mode 1