I came across a scenario where my boss wanted to change the default selection for security type in Outlook Web Access on a customer’s Exchange Server. By default the option “This is a public or shared computer” is selected and although this is a good idea for most organizations to keep as a default for security reasons our needs were slightly different.

Fig 1. Default setting in OWA

We are creating a separate CAS server for internal Customer Service staff and want to have a different look and feel for the logon page to the External facing OWA site (and also the less secure and time stringent setting as a default)

So here is what i found and the correct way to change the default setting to “This is a private computer”

On the CAS server you will need to navigate to C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\Owa\auth in windows explorer and look for a file called logon.aspx

I would recommend that you copy this file elsewhere rather than trying to edit the “live” file or try this out first in a lab environment before putting it into production. Next search the text file for a line with the following text <td><input id=”rdoPblc” type=”radio” name=”trusted” value=”0″ onclick=”clkSec()” checked></td> now cut the text saying “checked” (and the space before) and paste it into the line saying <td><input id=”rdoPrvt” type=”radio” name=”trusted” value=”4″ onclick=”clkSec()” paste the cut text here></td> the line should now look like this:

<td><input id=”rdoPrvt” type=”radio” name=”trusted” value=”4″ onclick=”clkSec()” checked></td>

Save the file back to the location where you copied it from (after renaming the original to something like logonold.aspx) and then open your web browser and access the OWA website and you will see that the option ”This is a private computer” is checked by default.