server name in window.open

Hi everyone, I'm using a script command in my ASP intranet page.   The command is simple:

<script>window.open("myfilename.asp","mywindow")</script>

All was working fine until I have change my server name from "svradm" to "srvhadm" because when using window.open command, it tries to open the file in "srvadm".  

I need this command to open the right file or, at leat, that I can specify where the file is located?   Even when specifying directly svrhadm:80 in the code, it still doesn't wan't to open the file on the new server.

My feeling  is that there is some kind of variable I need to set in windows on my server but I have no idea where.

thank you for helping