Hostname Aliases in XP Pro

In XP Pro how can I create a local alias for hostnames of some other computers on the domain?

When I created an entry in any of hosts, lmhosts, or lmhosts.sam, I can ping a computer with the alias, but when I attempt to connect to a file share \\alias_name\share_name, I get the following error:

\\alias_name
You were not connected because a duplicate name exists on the network. Go to System in Control Panel to change the computer name and try again.

I can connect to \\host_name\share_name with or without the alias in the hosts file.

I simply want the aliases on my computer for convenience so I don't have to remember or look up specific computer hostnames in a spreadsheet I keep for information on our ~50 computers.

Note: I am not a domain admin, and I don't believe this issue is important enough to ask to have it changed at their level.

EDIT:
The following is output from nslookup showing the alias does not already exist as a hostname. The output was the same regardless of an entry being in the hosts file. (I masked information below.)

C:\Documents and Settings\USER>nslookup host_name
Server:  xxxx-ns.xxxx.com
Address:  ###.###.###.50

Name:    hostname.xxxx.com
Address:  ###.####.###.19

C:\Documents and Settings\USER>nslookup alias_name
Server:  xxxx-ns.xxxx.com
Address:  ###.###.###.50

*** xxxx-ns.xxx.com can't find alias_name: Non-existent domain

EDIT2: Hosts file

127.0.0.1       localhost
###.###.###.14  alias_name

The "duplicate name exists" error is because the (NetBIOS) name of the Windows computer conflicts with some other name on the network. The instructions tell you how to resolve the issue - Go to System in Control Panel to change the computer name and try again.

You need to change your computer's name since windows won't allow PCs to have the same name in the same workgroup.

You will need to reboot to flush everything out.