Google Error Code 2.1a: A Quantcast Choice Guide to Protecting Your Ad Revenue

Google error code 2.1a
Google error code 2.1a

At Quantcast, we take data privacy very seriously. This inspired us to be one of the driving forces behind the IAB Europe’s Transparency and Consent Framework (TCF) and build one of the first-ever consent management platforms (CMPs), Quantcast Choice® based on the TCF standard.

The Quantcast Choice team has continually supported publishers and advertisers over the past few months as they’ve migrated to IAB TCF v2.0. As part of this, we are supporting the efforts of our customers to integrate with major ad tech leaders, including Google.

Since Google began operating on TCF v2.0 last month, many publishers have received error messages from Google, which has caused some confusion. To sort through some of these issues, we’ve created a guidance document to explain and help resolve the most common error codes. We know that these transitions can be complicated and we are here to help publishers adjust as smoothly as possible.

One of the most common errors we see with Choice customers integrating with Google is Error 2.1a, which occurs when Google ad tags are fired on a site before a consumer has had a chance to input their preferences into the CMP. As a result, Google will not serve ads because they are not receiving a consent signal. If you have experienced this error, you probably know it has a big impact on your ad revenue. 

It takes a community to stay on top of these types of issues, and our team has been hard at work on a solution for this error. Here are some things you should know about Google Error 2.1a, as well as information about how we are helping publishers solve this issue. 

Why Does this Error Happen?

With the IAB TCF v2.0, it is imperative to check for consent before a personalized ad is served. This is sometimes taken care of by a vendor, or by the publisher themselves. 

Error 2.1a happens when Google tags are fired, Google checks for the tcfapi() consent values, and the consent values are not yet populated. If there are no consent values when the Google tag is fired, Google displays a 2.1a error to publishers in their Google AdSense or Google Ad Manager account. 

This can happen when Google tags are fired before a CMP tag, or a consumer has not responded to the CMP yet. Consumers may take a couple of minutes to read the text on a CMP and share their preferences, yet Google tags may take a maximum of 500ms to check for consent values in the tcfapi() API.

How can you fix it? 

With this error, tag sequencing is very important. Simply adding the Choice tag before adding the Google tag will not fix this issue because Google is expecting a response to the CMP before their tag is loaded on the page. Therefore, publishers must prevent all Google ad tags from firing until a response is obtained from Quantcast Choice. Then, the site owner should only fire Google tags for which the consumer has provided permission. It is best practice to prevent all Google tags from firing, and only load Google tags on the page for which the consumer has provided permission. A more detailed technical guide to fixing Error 2.1a is available here

If you are using the Quantcast Choice WordPress plugin, it’s important to note that it cannot stop other plugins from adding tags to a site (no plugin can). Instead the Quantcast Choice plugin collects and saves consent data and makes it accessible so that others can read it and make decisions based on consent provided by users.

When encountering errors like this with vendors on TCF v2.0, it’s important to ask your partners how they expect their tags to be fired in relation to the CMP to ensure the site operates in compliance with consumer and vendor expectations.

We know how important it is to protect your ad revenues and make decisions based on consent. Quantcast can help you manage operational risk so you can focus on core areas like creating great content, improving user experience, and growing your business.

Our team has helped thousands of publishers and brands respond to key privacy requirements on TCF v2.0. If you’re interested in getting started, sign up here. You can also contact us for dedicated support or questions about our product here.