In my working company we have a 3 Internet providers and interconnected with each other through switches. Every time some PC's suddenly can't browse to the internet but they have connection. I try to ping test the IP of 3 internet providers on each PC's and i get a good result(no request time out). Sometimes all PC's can browse/use the internet and some are not. Also the WIFI sometimes we can connect but sometimes can't. Our main connection is around 4mpbs and the 2 cisco wifi connected there(1st flr and 2nd flr). I don't know what to do. this is my everyday problem.
Athan, As other guys suggested, you would need to provide more information but you need to bear in mind that pinging and browsing are different.Also we don't know where you are pinging. Browsing first of all requires connectivity to the target node, do you have it? If yes, then drill down on other mechanisms. Does your DNS work? Can you resolve addresses? Did you try doing nslookup? You say some nodes can access while others can't. Is there a difference in their DNS configuration? Have you checked your devices' logs for any event that may give you a clue?
So I ended up asking more questions then you unfortunately.