Ramblings of a former IT Consultant

After a recent Exchange 2007 deployment, I was asked to make some modifications to OWA to make it more intuitive for some of the less technically-proficient users to make use of OWA more effectively, and to personalise the OWA site to the company.

In Exchange 2007, the business logic which renders OWA is contained within the Client Access Server (CAS) role. This is a new addition; in 2003, this logic was handled by the back-end mailbox servers, with HTTP requests simply proxied via the front-end servers which acted in a similar fashion to a gateway. Therefore, on a 2007 Server, you need to be modifying the login screen on your Client Access Server(s).

The location of the OWA static content is C:\Program Files\Microsoft\Exchange Server\ClientAccess\OWA. Before you begin making modifications, I would suggest you take a backup of this entire folder and store it safely. There is a lot of ASP.NET programming in the various files; unless you are a proficient .NET programmer, you could easily break your forms-based OWA logon and several other aspects of OWA with just a few wrong clicks.

The changes I made were as follows:

• I changed the header image on the front page (which says Microsoft Office Outlook Web Access) to include the company name below the text and the company logo in the upper right. This was particularly easy to modify using Photoshop, although any graphics editing suite would suffice.The file you need to take a backup of, then modify, can be found in the Current\themes\base folder below the ‘OWA’ directory referenced above. The file to modify is lgntopl.gif. It is in GIF format and opens in Photoshop as an Indexed image; if you are importing any graphics, you may need to change the image mode in Photoshop using the ‘View’ menu, to ensure colour content is retained.It looks particularly effective when the text for Company Name appears to the bottom right of the ‘Web Access’ line in the header image. That along with the addition of the company logo in the upper-right of the image personalises the OWA experience, and also acts as a potential security benefit – if users become used to seeing the header in this way, they may be deterred from logging in to any other OWA page which does not exhibit your modifications.
  
• The logon page can be modified too. It can be found in the Auth directory, and is quite aptly named logon.aspx. If you did not make a backup earlier, it is very important you take a backup of this file prior to making modifications. You will see why when you right-click the file and choose to Edit it using Notepad or Wordpad.The page is built around a standard HTML table, and it is particularly easy to pick through the content to find out what does what. If, like me, it is unclear to you at the beginning, simply comment out sections of code and refresh your OWA login page to notice the effect. The HTML comment tags are <!– to start a comment, and –> to end the comment. All the HTML code you wish the browser to ignore should be within the two tags – but there is no limit to the number of comment tags you can have per page.The features I removed from the login page was the  ‘Public/Private’ login option and the ‘OWA Light’ version. The company decided it did not wish for these features to be visible to users. As a result, all users would login with sessions of type ‘Public’, and OWA would determine whether it operated in Premium or Basic mode based on browser (IE6 or above works in Premium, all other browsers operate in the cut-down, no frills Basic mode).I also added the following as a new row inside the main table which makes up the page:<tr>
  <td style=”width: 100%;font-size: 14pt; text-align:center;”>
  <p align=”center”>Welcome to <company>”s Web Mail</p>
  </td>
  </tr>
  <tr><td><hr></td></tr>

  This added an additional line to the login page, once again to personalise OWA to the company.

Once you are happy with your changes, I suggest you make a note of exactly what changes you made. When any new Service Pack or Update Rollup applied to the server, it is likely the OWA files will be overwritten when the CAS role is upgraded, meaning you must implement your changes again. I do not advise that you copy/paste the original files back into their previous location for the simple reason that any SP/UR may upgrade these files, and overwriting them with your originals from the previous patch level will revert these changes.

I hope you have learnt something from this blog posting, and I look forward to hearing back from you as to how you have taken these modifications further with your OWA pages. You are not just limited to modifying the login page; within the ‘OWA’ directory there are plenty of other pages which can have changes made to them, and you can also access all the images which produce the various default themes and modify these as you wish.