Yesterday afternoon (23rd May) Google Tag Manager suffered a serious issue. A large number of containers (including some of our clients) were mysteriously deleted by a blank user.
We noticed this by chance, not through a notification from Google. The deletions also appeared to occur at random worldwide, and we advise you login to your account as soon as possible to check if your account has been affected.
In cases where containers were deleted the tag manager account remained in place as normal, only the container was gone. Using the Google Tag Assistant extension for Chrome we could confirm that the containers had been completely deleted, and not just turned invisible.
There are many users on the Google Product Forums who have this issue, with the longest thread filled with concerned users.
While the issue seems to have been resolved, we strongly recommend making a backup of your container immediately in case the deletions occur again. To do this, login to your tag manager account and select admin from the menu at the top of the screen. From here, select ‘Export Container’, select the latest version and download the file. Be sure to do this for each container if you have more than one.
Google have acknowledged these issues on their status page, but have not provided any meaningful detail as of yet, which we find slightly concerning. They have however, said they do not believe it is a security breach.
Affected containers have been restored overnight, and although they weren’t immediately visible in the accounts, all accounts do appear to have returned to normal. It is however, worth keeping an eye on your account, and making sure the data recorded in Analytics seems accurate.
The most immediate problem this issue has caused is the loss of user data being recorded. The most common use of Tag Manager is to record all visits to a website. In affected accounts, this means no visitor data was recorded for much of yesterday afternoon.
While the loss of pageviews is not ideal, a far more serious problem is that many of these accounts would have been set up to record Ecommerce/conversion data, which will have been lost in the same way.
In our case, we run PPC campaigns for some clients who have been affected. We now have no Analytics data for yesterday afternoon for these campaigns, so it is impossible to determine key metrics such as conversions, bounce rate and time on site.
We eagerly await news from Google about this issue how and why it occurred. Until then, we are simply keeping a close eye on our Tag Manger accounts, to ensure all seems well.