You will need to use your new wireless router as an access point.
Do not change any settings on your current modem/router.
Before you connect the new hardware to the existing modem/router configure the new router as follows:
You will need to disable the WAN and DHCP on the wireless router.
Configure the LAN address to be a static address within your current network range (i.e. 192.168.0.xxx); But not within the dynamically assigned range. Subnet mask should be the same as all other devices on the network 255.255.255.0.
When the above is set, then go an plug a LAN port on the new box into a LAN port of the existing setup. You may need a crossover cable if your routers do not support auto-MDX. (DO not plug in the WAN port of the new box to a LAN port of the existing setup)
Then you can start working with the wireless configuration.
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