How can you use Location Extensions for just some of your Campaigns?
Since Location Campaign Extensions are only available when the Account-level Extension is enabled, this is actually quite the challenge! It appears that some situations allow you to add Campaign extensions in the absence of an Account Extension (like if you're an AdWords chat rep, apparently), but for the rest of us... You have to have the Account Extension, then you have to exclude the Extension on all of the Campaigns you don't wish to have the Extension active. This is accomplished from the Ad Extensions tab, just like adding one. However, once you click "Add Extension", you can select "Disable" from the drop down. If you do this with multiple Campaigns selected, you can do it all at once, at least. If you don't do this, then your Extensions will be active, if nearly hidden, collecting clicks for CPCs you probably didn't intend.
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