Using A PC As A Router Between Two Networks?

I have two networks that are on two different IP ranges, sharing an ADSL internet router.I can make the two networks access the internet through a Windows 7 PC acting as a router with two NICs, but I cannot print to a shared network printer (build in NIC in the printer).This is how it looks.

ADSL router IP:
IP address: 10.10.10.253
Subnet Mask: 255.255.255.0

Network A computers:
IP range of: 10.10.10.XXX
Subnet Mask: 255.255.255.0
Default Gateway: 10.10.10.253

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Note: All the computers can access the internet just fine, it's only the one set of computers on IP range 172.16.0.XXX that cannot see the printer.All computers are Windows 7 32bit Professional.