When i do a request submition to an Aspx page using the Ajax concept i get

request.status = 404

on the response text = "The resource cannot be found"
on the response body some gibrish text "浴㹬਍格慥㹤਍"

and sometimes i get
request.status = 200
and no problems accured.

this happense irregulary , sometime it works and sometimes it doesn't.

i think it has to do something with the relative aspx pages being called from the added Jscript on a page.
since i have pages using this from different locations and folders i can't get the consistency reqired.

i use this relative links:
var url = "~AjaxPages/CountryTeamsAjaxServer.aspx?countryname="+ID;
don't work

var url = "~/AjaxPages/CountryTeamsAjaxServer.aspx?countryname="+ID;
don't work

var url = "../AjaxPages/CountryTeamsAjaxServer.aspx?countryname="+ID;
works only when calling pages located inside sub-folder from root

var url = "AjaxPages/CountryTeamsAjaxServer.aspx?countryname="+ID;
works only when calling from pages located inside the root

can someone help me with that? i'm holding this problem for the last two months or so.