Troubleshoot creative delivery with Fiddler

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If you have a creative that isn't delivering properly, there is either a problem with how the line item or creative was trafficked, with the creative's code, or with the DoubleClick ad server.

A good way to figure out where the problem lies is to install a free third-party application called Fiddler (requires Windows) and use it to find the cause of the problem.

You can use Fiddler to display the creative code returned by the DoubleClick ad server. Using that code, you can create a test page to see if the creative renders properly without involvement from DFP. (Because DFP isn't involved, the test page doesn't go through the normal ad selection process, and DFP features such as competitive exclusion rules don't apply.)

If the creative still isn't rendering properly, you can use Fiddler to inspect the requests sent from your browser to the ad server.

1. Download Fiddler

If you are running Windows, you can download Fiddler from http://www.getfiddler.com/dl/Fiddler2Setup.exe (See the Fiddler website for more information.)

2. Inspect calls made from your browser to the DoubleClick ad server

When the creative isn't delivering at all, it may be because of a problem with the DoubleClick ad server. You can use Fiddler to inspect ad calls made to the ad server to see if they are unsuccessful.

To use Fiddler to inspect ad calls to the DoubleClick ad server:

  1. Open Fiddler.

  2. Open a browser and then open the web page where the line item isn't delivering.

    Fiddler displays the list of requests made by your browser.

  3. In the Web Sessions pane on the left side, look for the ad tag that's requesting the third-party creative.

    Here's an example of what the requests will look like:

    # Result Protocol Host URL
    13 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=top;tile=1;ord=1234567890?
    18 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=left;tile=2;ord=1234567890?
    21 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=right;tile=3;ord=1234567890?
    27 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=bottom;tile=4;ord=1234567890?
    29 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=center;tile=5;ord=1234567890?

    Successful requests to the DoubleClick ad server are indicated by the number 200 displayed in the Result column.

  4. If any call has a result other than 200, look at the URL column and check to make sure the ord and tile values are set up properly:

    • Are the tile values in descending order?
    • Are the ord values all matching up?
    • When you refresh the page do you get a different ord value for all the ad calls?

    Work with your developer to fix any problems with tile and ord values.

  5. If the tile and ord values are set up correctly and the line item still isn't delivering, continue to 'Get the creative code', below.

3. Get the creative code

You can display the code that's returned from the DoubleClick ad server to create a test page and check how the creative renders without involvement from DFP or, in the case of third-party creatives, to send to your advertiser who can then troubleshoot the problem with their creative developer.

To get the creative code:

  1. Open Fiddler.

  2. Open a browser and then open the page on your website where the creative isn't delivering properly.

    Fiddler displays the list of requests made by your browser.

  3. In the Web Sessions pane on the left side, click the ad tag that's requesting the creative.

    Here's an example of what the requests will look like:

    # Result Protocol Host URL
    13 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=top;tile=1;ord=1234567890?
    18 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=left;tile=2;ord=1234567890?
    21 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=right;tile=3;ord=1234567890?
    27 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=bottom;tile=4;ord=1234567890?
    29 200 HTTP ad.doubleclick.net /adj/mnhb.homepage/home;pos=center;tile=5;ord=1234567890?
  4. Click the Inspectors tab on the top-right pane.

  5. Below the Inspectors tab, click the Headers tab.

  6. In the bottom-right pane, click the Text View tab.

  7. You’ll see a message that says “Response is encoded and may need to be decoded before inspection.” Click on that message.

    The creative code that the ad server returned to this ad tag on your page displays. Now you can copy the code to create a test page or send the code to your advertiser for further investigation.

4. Create a test page

Using the creative code you displayed in 'Get the creative code', above, you can create a test page and check if the creative renders properly without involvement from DFP or the third party.

To create a test page:

  1. Highlight and copy the code you displayed in Fiddler in 'Get the creative code', above.

  2. Open Notepad++ or another code editor and place this code in a new blank file:

    <html> <body> <script type="text/javascript"> </script> </body> </html>
  3. Paste the creative code returned from Fiddler under <script type="text/javascript">.

    Your test file should now look like this:

    <html>
    <body>

    <script type="text/javascript">

    document.write('<a target="_blank" href="http://thirdpartyadserver.com/click;h=v8/3a1b/0/0/%2a/e;141717700;0-0;1;21350020;3-125/125;22864899/22882782/1;;~sscs=%3fhttp://www.expedia.com"><img src="http://s0.2mdn.net/viewad/1578030/33093/Cartmen+Air+125x125.gif" border=0 alt="Click here to find out more!"></a>');

    </script>
    </body>
    </html>
  4. Save the file as an HTML file. To recreate normal ad serving behavior, have your web developer or webmaster upload this file to a test server.

  5. Once the file is uploaded to the test server, open it in a browser. Remember to open the file from the test server and not your computer.

  6. Observe how the ad serves from the third party with no DFP involvement.

    If you don't have a problem viewing this file from the HTML file you just created, then review how the ad is set up in DFP and check your ad tags. If the problem persists when you view the HTML file, then you can be sure that the issue is with the code. Contact either your creative developer or the advertiser so they can ask their creative developer to resolve the issue.

5. Save the Fiddler session and send it to others to get more help

Save the Fiddler session by clicking Save. Once you’ve saved a Fiddler session, you can send it to a colleague or a member of the DFP Support team for troubleshooting help.

If you have a third-party creative that's still not delivering properly, see Troubleshoot third-party creatives for more steps you can take.