we have about 100 users on the inside interface of a PIX 525. Everyone is able to get to the internet then, someone will come to me saying they can not pop mail or browse the web. I can ping all the computers on the inside but can not ping outside. Once I clear the xlate of the firewall, they are able to connect without a problem. Everything will be working fine for a while then the same thing happens. I have dropped the xlate timeout for 30min, but that does not resolve the issue. For a test I had a enduser who could not get online wait an hour (the xlate is suppose to timeout after 30min) and they still could not connect. I had to manually clear the xlate before they could. I have to find a solution for this soon. Please help