diff --git a/src/core/init.php b/src/core/init.php
index b35a251..a94124c 100644
--- a/src/core/init.php
+++ b/src/core/init.php
@@ -33,7 +33,8 @@ class Init {
     }
     // merge the default config with the custom config
     Core::$Config = array_merge($default_config,$config);
-
+    Core::$Config["PrimaryDomain"] = Core::$Config["Domain"][0];
+    
     // parse the default services file for default values
     $default_services = parse_ini_file(Core::root_dir()."/default-config/services.default.ini", true);
 
diff --git a/src/core/init/responder.php b/src/core/init/responder.php
index eb06e49..e3c394f 100644
--- a/src/core/init/responder.php
+++ b/src/core/init/responder.php
@@ -65,6 +65,19 @@ class Responder {
     }
     return $resp;
   }
+  private function get_username($service,$email_address) {
+    $username = "%EMAILADDRESS%";
+    if(!$service["UsernameIsFQDN"]) {
+
+      preg_match("/^[^@]+/",$email_address,$matches);
+      if (count($matches) > 0){
+        $username = $matches[0];
+      }
+    } else if ($service["RequireLogonDomain"]) {
+      $username = preg_replace("/[^@]+$/",Core::$Config["LogonDomain"],$email_address,1);
+    }
+    return $username;
+  }
   private function all_urls(){
     $response = new Response();
     // Not really useful, unless some lovely app developers want to parse it for their app :)
diff --git a/src/public/autoconfig.php b/src/public/autoconfig.php
index 3d91f35..767abb2 100644
--- a/src/public/autoconfig.php
+++ b/src/public/autoconfig.php
@@ -1,95 +1,64 @@
 <?php
-
-// Errrrrrrrrgh, this is sooooo messy, I'm going to tidy this up
-// It's basically configuring the format of the email address dependent on
-// variables set in the config file.
-// i.e. if the domain isn't required for authentication then it strips the
-// username back to just the pre-@ part. Or, if the username requires a different
-// logon domain, then it replaces the email domain with the localdomain
-//
-// TODO: TIDY THIS UP!!
-$conf = Core::$Config["Services"];
+// Get some core information to help with generation.
+$services = Core::$Config["Services"];
 $data = Core::get_get_data();
-$email_provided = false;
-$display_name = false;
-$emailaddress = false;
 if (isset($data["emailaddress"])) {
   $email_address = $data["emailaddress"];
-  $display_name = $email_address;
-  $email_provided = true;
-} else if ($data["path"]) {
-  $query = parse_url($data["path"]);
-  if (isset($query["query"])){
-    $email_address = explode("=",$query["query"]);
-    if ($email_address[0] == "emailaddress") {
-      $email_address = $email_address[1];
-      $email_provided = true;
-      $display_name = $email_address;
-    }
-  }
 }
-if ($email_provided) {
-  if(!Core::$Config["RequireAuthDomain"]) {
-    $email_address = str_ireplace("@".Core::$Config["Domain"],"",$email_address);
-  } else if (Core::$Config["LogonDomain"]) {
-    $email_address = str_ireplace(Core::$Config["Domain"],Core::$Config["LogonDomain"],$email_address);
-  }
-}
-
 // The below link has config-v1.1.xml information
 // https://wiki.mozilla.org/Thunderbird:Autoconfiguration:ConfigFileFormat
 ?>
 <clientConfig version="1.1">
- <emailProvider id="<?php echo Core::$Config["Domain"][0]?>">
+ <emailProvider id="<?php echo Core::$Config["PrimaryDomain"]?>">
    <?php foreach (Core::$Config["Domain"] as $domain){ ?>
    <domain><?php echo $domain; ?></domain>
    <?php } ?>
-   <displayName><?php echo $email_provided ? $display_name : "%EMAILADDRESS%" ;?></displayName>
-   <?php if($conf["InMail"]&& $conf["InMail"]["Enabled"]){
-     $in = $conf["InMail"]; ?>
-     <incomingServer type="<?php echo strtolower($in["Type"]);?>">
-       <hostname><?php echo $in["Server"];?></hostname>
-       <port><?php echo $in["Port"];?></port>
-       <socketType><?php echo $in["SocketType"];?></socketType>
-       <username><?php echo $email_provided ? $email_address : "%EMAILADDRESS%";?></username>
-       <authentication><?php echo $in["Authentication"];?></authentication>
+   <displayName>%EMAILADDRESS%</displayName>
+   <?php if($services["InMail"]&& $services["InMail"]["Enabled"]){
+     $service = $services["InMail"]; ?>
+     <incomingServer type="<?php echo strtolower($service["Type"]);?>">
+       <hostname><?php echo $service["Server"];?></hostname>
+       <port><?php echo $service["Port"];?></port>
+       <socketType><?php echo $service["SocketType"];?></socketType>
+       <username><?php echo $this->get_username($service,$email_address); ?></username>
+       <authentication><?php echo $service["Authentication"];?></authentication>
      </incomingServer>
    <?php }
-   if($conf["OutMail"]&& $conf["OutMail"]["Enabled"]){
-     $out = $conf["OutMail"]; ?>
-   <outgoingServer type="<?php echo strtolower($out["Type"]);?>">
-     <hostname><?php echo $out["Server"];?></hostname>
-     <port><?php echo $out["Port"];?></port>
-     <socketType><?php echo $out["SocketType"];?></socketType>
-     <username><?php echo $email_provided ? $email_address : "%EMAILADDRESS%";?></username>
-     <authentication><?php echo $out["Authentication"];?></authentication>
+   if($services["OutMail"]&& $services["OutMail"]["Enabled"]){
+     $service = $services["OutMail"]; ?>
+   <outgoingServer type="<?php echo strtolower($service["Type"]);?>">
+     <hostname><?php echo $service["Server"];?></hostname>
+     <port><?php echo $service["Port"];?></port>
+     <socketType><?php echo $service["SocketType"];?></socketType>
+     <username><?php echo $this->get_username($service,$email_address);?></username>
+     <authentication><?php echo $service["Authentication"];?></authentication>
    </outgoingServer>
    <?php }
-   if ($conf["AddressBook"] && $conf["AddressBook"]["Enabled"]) {
-     $card = $conf["AddressBook"]; ?>
-    <addressBook type="<?php echo strtolower($card["Type"]); ?>">
-      <username><?php echo $email_provided ? $email_address : "%EMAILADDRESS%";?></username>
-      <authentication><?php echo $card["Authentication"] ? $card["Authentication"] : "http-basic" ;?></authentication>
-      <serverURL><?php echo $card["Server"];?></serverURL>
+   if ($services["AddressBook"] && $services["AddressBook"]["Enabled"]) {
+     $service = $services["AddressBook"]; ?>
+    <addressBook type="<?php echo strtolower($service["Type"]); ?>">
+      <username><?php echo $this->get_username($service,$email_address);?></username>
+      <authentication><?php echo $service["Authentication"];?></authentication>
+      <serverURL><?php echo $service["Server"];?></serverURL>
     </addressBook>
     <?php }
-    if ($conf["Calendar"] && $conf["Calendar"]["Enabled"]){
-      $cal = $conf["Calendar"] ;?>
-    <calendar type="<?php echo strtolower($cal["Type"]);?>">
-      <username><?php echo $email_provided ? $email_address : "%EMAILADDRESS%";?></username>
-      <authentication><?php echo $card["Authentication"] ? $card["Authentication"] : "http-basic" ;?></authentication>
-      <serverURL><?php echo $card["Server"];?></serverURL>
+    if ($services["Calendar"] && $services["Calendar"]["Enabled"]){
+      $service = $services["Calendar"] ;?>
+    <calendar type="<?php echo strtolower($service["Type"]);?>">
+      <username><?php echo $this->get_username($service,$email_address);?></username>
+      <authentication><?php echo $service["Authentication"];?></authentication>
+      <serverURL><?php echo $service["Server"];?></serverURL>
     </calendar>
     <?php }
-    if ($conf["WebMail"] && $conf["WebMail"]["Enabled"]) {
-      $wm = $conf["WebMail"]; ?>
+    if ($services["WebMail"] && $services["WebMail"]["Enabled"]) {
+      $service = $services["WebMail"]; ?>
     <webMail>
-      <loginPage url="<?php echo $wm["Server"];?>" />
-      <loginPageInfo url="<?php echo $wm["Server"];?>">
-        <username><?php echo $email_provided ? $email_address : "%EMAILADDRESS%";?></username>
-        <usernameField id="<?php echo $wm["UsernameDivID"];?>" name="<?php echo $wm["UsernameDivName"];?>" />
-        <passwordField name="<?php echo $wm["PasswordDivName"];?>" />
-        <loginButton id="<?php echo $wm["SubmitButtonID"];?>" name="<?php echo $wm["SubmitButtonName"];?>"/>
+      <loginPage url="<?php echo $service["Server"];?>" />
+      <loginPageInfo url="<?php echo $service["Server"];?>">
+        <username><?php echo $this->get_username($service,$email_address);?></username>
+        <usernameField id="<?php echo $service["UsernameDivID"];?>" name="<?php echo $service["UsernameDivName"];?>" />
+        <passwordField name="<?php echo $service["PasswordDivName"];?>" />
+        <loginButton id="<?php echo $service["SubmitButtonID"];?>" name="<?php echo $service["SubmitButtonName"];?>"/>
       </loginPageInfo>
     </webMail>
     <?php } ?>