Request time out

We have a new system, and we try to pass our data through
ODBC we only provide a database name, server name, and an
IP address of our internet server.Then we have a warehouse
which is far from our office, thats why we used a router.
My problem is when i try to ping our internet server it replies
request time out, but when I call our office where our server
was located they can still connect to the internet, and in the
warehouse i can also connect to the internet. Before when
I ping our internet server it will reply.Pls advice me what to do
it really affect our processes...thanks a lot...