What Pool, what OS, what CPU, and what temperatures? Mine runs 24/7 without problems.
I'm mining with win7 64bit, i7 3970k, temps are ok (60°), on nexusminingpool.
edit: i've just tried with cestballot pool, and it's working

thanks for your help!
Strange. nexusminingpool gets anywhere from 300-1000 connections and I've not heard of anyone else having trouble before. What error do you get? Is there anything in debug.log?
nexusminingpool works like my pool
http://nexusniropool.cestballot.fr/ . If your miner works on my pool it will work on nexusminingpool. Could we see you launch files for nexusminingpool and nexusniropool.cestballot.fr? (.bat)
miner setting :
coinshield_prime.exe Pool_IP port your_address nb-threads
example for start.bat for nexusminingpool :
coinshield_prime.exe nexusminingpool.com 9549 2xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx5M 10
example for start.bat for nexusniropool.cestballot.fr :
coinshield_prime.exe 51.255.38.3 9549 2Sxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxfv 10
Now nexusminingpool have a nice cpu power. You can use it. Today nexusminingpool is one of the bigest Nexus pool. We realy appreciate this cpu power share on all Nexus pool, the network love it
