Try changing the Channel number in the router's wireless settings in case something on the same frequency is interfering with the signal.
<<< I have tired disabling the the DHCP setting and typing the server in and then it will connect, but the web doesn't work.>>>
If you want to use a fixed IP address it must be a unique one in the same subnet (IP address range) as the router. For example, if the router's IP address is 192.168.0.1 then you could use something like:
IP address - 192.168.0.25
Subnet Mask - 255.255.255.0
Default Gateway - 192.168.0.1 (the router's IP address)
DNS Server - 192.168.0.1 (the router's IP address)
Just ensure the third "octet" (number) in the IP address is the same as the router's.