Why does this happen?
Caching of the tracking script will prevent any updates to be reflected on your site.
Solving the Error
If you are using a Cache plugin on your site, you will need to clear the cache for the site to update with the new plugin information for our system (and any other additions you might have made).
The most common platform where Caching can be an issue is on WordPress sites. WordPress sites are typically heavily cached and therefore will not update the live public version of your site with changes right away. Therefore, checking the installation right after you've activated the Crazy Egg plugin may result in a false negative.
If you are still having trouble, please send us an email. Please include the name of the Snapshot and page URL.