Blocking accounts with high bounce and complaint rates
Sitecore Send detects bounce rates and complaint rates to protect users and the infrastructure. When you exceed any of the thresholds, Sitecore Send automatically blocks your account from sending another campaign and sends you an email notification to inform you that your account is on hold. The Sitecore Send Deliverability team is added to the CC field of the email notification and you can use this address to get assistance with your account.
The Deliverability team reviews suspended accounts and investigates why the campaign exceeded bounce and complaint thresholds. Accounts are reviewed during business hours, Mondays to Fridays, from 6:00 to 14:00 UTC.
While your blocked account is suspended and under review, it is still active, and you can use other Sitecore Send features. However, you cannot send any campaigns.
Sitecore Send temporarily blocks suspicious accounts and disables sending of campaigns for two reasons. Firstly, to protect the sending reputation and safety of all Sitecore Send users. If an Internet Service Provider (ISP) detects a high bounce or complaint rate from a particular sender of a Sitecore Send campaign, the ISP can block all other Sitecore Send email campaigns from being sent on their ISP. Secondly, while accounts are blocked, affected users can clean up their lists and investigate possible issues with their subscription sources. A well-maintained email list guarantees better delivery and deliverability rates.