I can't see anything particularly wrong with the config. Its basic and it should work. You say that you cannot access files on the PC on the other network, does that mean there is no communication between the 2 hosts what so ever? Can you ping between the hosts? Have you configured the correct ip information on the hosts, particularly the default gateway?
We need to know more about how it is setup ie. do you have a separate switch connected to each interface of the router ?
Do the clients have the default gateways set to be the router interface IPs ?
When pinging to a computer make sure any firewalls are turned off as this can block ICMP.
Okay well the default gateways for both set of computers are not the router interface IPs so that's why it's not working.
I suspect the 10.22.227.254 IP is the modem but I have no idea what the 10.22.226.254 IP is meant to be.
Can you clarify what those IPs are meant to be ?
Also do you know if your modem supports -
1) adding routes
2) doing NAT for non directly connected networks ie. 10.22.226.0/24
if it can't then we can do it all on the router but you are going to have to make a lot of changes.
You are right! I called the 3rd party company that manages our 10.22.227.X Network they said i need an ip address. They gave me 10.22.227.134 as the ip address.
So im assuming the 10.22.227.134 will be the ip address of the router??
I have uploaded an updated diagram as well.
As Jon quite rightly pointed out here the default gateway configurations on the hosts are incorrect. Please change it to the router interface for the respective networks.
I.e DG for the 10.22.226.0/24 network should be 10.22.226.1
10.22.227.1 for the 10.22.227.0/24 network
You need to think about what the routing logic would be from the hosts perspective, when it wishes to send a packet to another host it will compare the destination IP with its own IP. If the host is in the same subnet then it will ARP for the destination MAC and from that construct the L2 header information before sending it on its merry way.
If the destination is on a different subnet however it will want to send the packet to its default gateway, this is where in your case the host is unable to proceed as the default gateway config is invalid
Hope this helps.