Customising Exchange 2003 OWA FBA

It took some digging to find this. Basically I have an SBS box at home and I wanted to “fix” my domain name on the FBA form. Well I found plenty of other articles about customising OWA. Check this blog out https://blogs.msdn.com/tmeston/archive/2005/06/08/426824.aspx, But I stumbled accross the one I wanted, in really smartly named KB!

820378 Outlook Web Access session unexpectedly quits when forms-based authentication is used

Got down to Workaround and the follow Method 2. 

If you do not want to specify the domain when you log on, create a custom Logon.asp page that includes the default domain (either visible or hidden). You can also display a list of the domains that the server supports.

The following example code illustrates how to create a custom Logon.asp page. To use this code, replace both instances of <FORM> in each language-version of the Logon.asp file with the following code.

Note You must replace both instances of <FORM> with this code because one instance is for rich experience and the other instance is for basic experience. This replacement is required for browser compatibility. Also, if you make a custom Logon.asp page, users will no longer be able to log on with a user name of domain\user name. If they do this they will actually be passing domain\domain\user name.

Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements.

Important Microsoft does not provide assistance in customizing OWA objects and if you contact Microsoft about an OWA issue for a server that OWA is customized on, you must replace the customized files with the original versions of the files.
For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

327178 (https://support.microsoft.com/kb/327178/) Microsoft support policy for the customization of Outlook Web Access for Exchange

 <script Language=javascript>
 <!--
  function logonForm_onsubmit()
  {
   if (logonForm.username.value.indexOf("@") !=-1)
    {
     return true;
    }
   logonForm.username.value = " <name of NetBIOS domain here> \\" + logonForm.username.value;
   return false;
  }
 //-->
 </script>
 <FORM action="/exchweb/bin/auth/owaauth.dll" method="POST" name="logonForm" autocomplete="off" onsubmit="logonForm_onsubmit()">

Note In the script, make sure that you add the name of your network basic input/output system (NetBIOS) domain in the code. In the script that is provided, put your domain name in the <name of NetBIOS domain here> location.

NB: Make sure you read 327178 Microsoft support policy for the customization of Outlook Web Access for Exchange first and that you take a copy of logon.asp before you modify it!