Recently Google AdSense has updated its Manage Ads page and published a post Manage Ads gives you more ad functionality. Click on the following image for the full version:

How to Show AdSense Units

Now, you can clearly see that there are 2 checkboxes on the left hand side:

View your active AdSense units below. You can also import your old AdSense code to create saved AdSense units. Learn more...

[ ] Show inactive AdSense units [?]
[ ] Show hidden AdSense units [?]

Those check boxes allow you to view the inactive or hidden AdSense units.

How to Hide AdSense Units

Of course, it would be silly if you can show the hidden units but can't hide it. Google is smart enough to recognize the need and hence make the function for you. Previously you have to follow How to Delete AdSense unit in order to hide an ad unit. Now you don't have to.

How? You can see on the right hand side that there is a Hide link, which allow you to hide the AdSense unit on that row without actually deleting it. This is to prevent the code on some page you "might" have from breaking the AdSense system for showing unavailable ad units.

• How do I delete AdSense Ad Unit from the Manage Ads page?
• How do I remove AdSense unit from my web page?

How do I delete AdSense Ad Unit from the Manage Ads page?

It's written in this Official Google help page How do I delete an AdSense unit? that you can NOT delete the ad units from your Manage Ads page, but hide it. You can hide ad unit by following 2 steps:

1. Remove the unwanted ad unit's code from all your web pages to stop it from gaining impressions.
2. Wait 7 days for the ad unit to disappear from your Ad Manager.

How do I remove AdSense unit from my web page?

Answer:

The process is easy if you remember where you place the code. Otherwise you will need to find it. Follow these steps:

1. Open the file for the web page you placed the code in.
2. Locate the AdSense JavaScript code that you pasted into the page earlier. It look like this:

   <script type="text/javascript"><!--
   google_ad_client = "pub-01234567890123456";
   //120x240, vertical homepage
   google_ad_slot = "0123456789";
   google_ad_width = 120;
   google_ad_height = 240;
   //--></script>

   <script src="http://pagead2.googlesyndication.com/pagead/show_ads.js" type="text/javascript">
   </script>

3. Remove the above code from your web page.

Update on 22 Dec 2007: Now you can actively Hide and Show AdSense Units.