Question : The combination of IP address and subnet mask is invalid

the server is windows 2003. it's a rented server with public ip address. i am allowed to add additional ip address which can be used for different domain name. the server ip address is configured such as example:
ip: 74.209.15.14
subnet: 255.255.255.255
gateway: 10.255.255.1
dns: 195.20.224.234

i tried to add 74.209.15.20 to this server and i did the follow:
TCP/IP > Properties > Advanced > IP Addresses: add > i entered 74.209.15.20 and subnet mask 255.255.255.255.

i got below error message:

The combination of IP address and subnet mask is invalid. All of the bits in the host address portion of the IP address are set to 1. Please enter a valid combination of IP address and subnet mask.

Please help how to solve this problem. thank you.

Answer : The combination of IP address and subnet mask is invalid

PAQed with points refunded (250)

Computer101
EE Admin