You can now see and follow up on Mailchimp sync errors in the Add-ons section.
Mailchimp syncs can fail for various reasons. If a Mailchimp syn error occurs, you can fix it by for example ensuring the API key, lists, and emails are correct. Here is a list of possible reasons for failed syncs:
You have exceeded the maximum number of 30 merge fields for this list
This account has been deactivated
Your API key may be invalid, or you’ve attempted to access the wrong datacenter
XXX has signed up to a lot of lists very recently
XXX is already a list member
A Merge Field with the tag XXX
Your merge fields were invalid
You can only update email addresses for members with a status of XXX
It already exists on the list
Was permanently deleted and cannot be re-imported. The contact must re-subscribe to get back on the list.
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