How can we locate the codebase objects using Fiddler?

Hi everyone!

Gary Ranne here from the IE Team with a quick tip on how to use Fiddler to identify codebase objects on a webpage.

With the inception of the ActiveX installer service it is even more important to be aware of the location that ActiveX controls are being installed from. Frequently, this can be done simply by viewing the source of the Web page that is loading the control. All we need to do is to look for an Object tag that contains a “codebase” attribute. This “codebase” attribute points to the location that the control will be downloaded from. This works great when the Object is being loaded from the page itself, but it is not uncommon for a control to be loaded from a .js file or a .css file. How can we locate the codebase in these cercumstances?

  • Install Fiddler from
  • With Fiddler capturing, navigate to the page that is trying to load the control.
  • Once the page has tried to load the control, select all the sessions in Fiddler like so:

  • Decode all the selected sessions by right-clicking on the sessions and selecting Decode selected sessions
  • Next select the Edit menu / find sessions…
  • In the find dialog enter codebase” and click find sessions.
  • This should highlight any sessions that have a codebase attribute within it.
  • Select the highlighted session and display the raw tab in the response inspector

  • Click “View in Notepad” and then search in Notepad for the codebase.





The IE Support Team



Comments (0)

Skip to main content