Thanks for sharing your experience. However, there must be some serious issues with your current setup or approach. Please note that, email verification is not a magic "Green Card" for sending a ton of marketing emails. If you send 84k emails without following all the required steps, the emails will bounce as the service providers will start blocking you. The goal of email verification is to identify the active email addresses, not to prevent the blocks by service providers because of sending mass marketing emails without following the other rules. We have added a short list of important factors below. If they were not maintained correctly (especially for cold emails), the emails will bounce because of the service provider's spam filter.

1. Verification must be done via dashboard upload or using Power Mode in case of API (quick mode is for quick temporary emails and dead domain filtering, along with some other checks).

2. Your email server and domain must be configured correctly with proper DKIM, SPF and PTR records in place.

3. The IP must have a good reputation for sending emails (in that case, this is owned by SendFox, in your case, not really in your control).

4. Email content must look like genuine emails. If the content looks like a generic mass marketing email, nowadays, many email service providers can block you by marking it as spam. In some cases, the provider may block an email even if the message contains a generic redirect/tracking link in it. A properly placed unsubscribe link and header are also required to comply with the standards of most email service providers.

5. For cold email marketing, email warm-up is another very important factor. You must warm up your email address to build trust. Still, you should not send more than a certain number of emails from each of your addresses in a day. The goal is to make it look natural.

6. Some of the users may still mark your message as spam manually. In such case, he providers may still block you if there are many complaints.

We are not sure how well you maintained the above-mentioned things, as you have not shared any technical details with us. We also have not found any support request from you on our end.

We kindly request you to contact us at [email protected] and let us know some more details about the approach you followed, along with some of the bounced email addresses. We will do a manual analysis from our end and will give you the full report. Even if you do not use our service in the future, hopefully, you will get some clear idea about what was wrong and what to fix to reach your goal.

We will be waiting for your response. Thanks.