imageupload works in local but does not work in server - ajax

Question

I want to upload a image on server.I use ajax and webmethod, It works when I run code in local host but when I upload it in server it does not work.
I guess there are some problems in my webmethod but I could not find it.
function savefile(location, files, method_name) {
var data = new FormData();
var webmethod = "../WebService.asmx/" + method-name;
if (files.length > 0) {
data.append("UploadedFile", files[0]);
data.append("location", location);
}
var ajaxRequest = $.ajax({
type: "POST",
url: webmethod,
enctype: 'multipart/form-data',
contentType: false,
processData: false,
data: data
});
}
<WebMethod(EnableSession:=True)> _
<ScriptMethod(ResponseFormat:=ResponseFormat.Json)>
Public Function savefile() As String
Try
Dim result As String = ""
Dim pdf As String = ""
If HttpContext.Current.Request.Files.AllKeys.Any() Then
Dim httpPostedFile = HttpContext.Current.Request.Files("UploadedFile")
If httpPostedFile IsNot Nothing Then
Dim location = HttpContext.Current.Request("location")
Dim extension As String = System.IO.Path.GetExtension(httpPostedFile.FileName)
Dim filename_widthout_extension As String = httpPostedFile.FileName.Substring(0, httpPostedFile.FileName.Length - extension.Length)
Dim file_name = httpPostedFile.FileName
Dim fileSavePath = System.IO.Path.Combine(Server.MapPath(HttpContext.Current.Request("location").ToString), filename_widthout_extension + postfix + extension)
result = (location + "/" + filename_widthout_extension + extension).ToString.Substring(2)
httpPostedFile.SaveAs(fileSavePath)
location = httpPostedFile.FileName
End If
Return ""
Catch ex As Exception
End Try
End Function