Have had ADSL installed through a router, connected the wireless router and it works fine
Have since connected the original router via -120mtrs of CAT5 cable to extend to the house. Connection through LAN is fine into desktop however the minute we try to connect an additional wireless router the connection fails. We have even put the LAN from the second Wireless into the desktop and there is no connectivity.
We have had a technician come to sort the problem, they advise that they have no explanation as to why the LAN works from the distance but the wireless does not. They have suggested that we need to cut the CAT5 half way and put an antenna up to connect the two routers.
The Ethernet cable is a bit long but it seems odd that it would cause that problem. How are you attaching and configuring the AP point? LAN to LAN is correct and then turn off DHCP in the AP and assign it an IP address that is either (1) reserved dynamic, or (2) static in the network but outside the DHCP assignment range. Use the same SSID and pass key as the main router but use different radio channels.