When using Digital Ocean for sending emails, addressing Microsoft IP blocklisting requires understanding the scope of the block; if it's Digital Ocean's issue, they need to resolve it. It's crucial to identify and fix the underlying causes of blocklisting, like spam complaints, high bounce rates, or sending to spam traps. Actively monitor your IP and domain reputation using tools and establish feedback loops with ISPs. Be aware of the negative reputation often associated with Digital Ocean IPs. For Microsoft delisting, use their portal after fixing the problems. Avoid using SMTP for mailbox validation to prevent further issues. Use dedicated IPs and properly configure SPF, DKIM, and DMARC. Consider third-party email services like SendGrid or Mailgun. For email validation, use services with batch processing, validate addresses, double opt-in processes, and clean your list regularly. Warming up your IP gradually is beneficial, and monitoring bounce rates along with sender reputation are important. Consider also segmenting lists and understanding validation APIs might use questionable tactics, while SMTP verification (although flawed) is a better option than regexes. Adhere to Google's bulk sender guidelines.
10 marketer opinions
When using Digital Ocean for email sending, it's common to encounter IP blocklisting issues with Microsoft. To address this, avoid sending validation emails via SMTP as it may worsen the issue. Instead, consider using a dedicated IP address, properly configuring SPF, DKIM, and DMARC for authentication, and utilizing reputable third-party email services like SendGrid or Mailgun that manage IP reputation for you. For email validation, consider using services that offer batch processing to handle bulk validation efficiently and research different email verification services to find one that suits your needs. Implement a double opt-in process, regularly clean your email list, monitor bounce rates, segment your list based on engagement, and monitor your sender reputation through tools like Sender Score to avoid spam traps and improve overall email deliverability.
Marketer view
Email marketer from Stackoverflow shares that for bulk email validation, consider using a service that offers batch processing to validate multiple email addresses simultaneously. This can save time and resources compared to validating each address individually.
13 Jul 2021 - Stackoverflow
Marketer view
Email marketer from Email Geeks shares that asking Microsoft or any other MBP to unblock your IPs so you can do mailbox validation via SMTP will just get you more in trouble and MBPs will like you even less…
17 May 2023 - Email Geeks
6 expert opinions
When addressing Microsoft IP blocklisting issues while using Digital Ocean, it's important to first determine the scope of the block. If it's a wider Digital Ocean block, they need to resolve it; SWIPing your IP might help. Understand the root cause of the blocklisting, such as spam complaints or high bounce rates, and rectify those issues. Monitor your IP and domain reputation using available tools, identify negative trends, and establish feedback loops with ISPs. Be aware that Digital Ocean IPs are often associated with spam. Be cautious when using email validation APIs due to questionable practices like botnets or buying data from ESPs. While SMTP testing for email validation has issues, it's considered a better validator than regexes.
Expert view
Expert from Word to the Wise suggests monitoring your IP and domain reputation using various tools and services. Identify any negative trends or issues that could contribute to blocklisting or filtering. Also establish feedback loops with ISPs to address issues proactively.
3 Feb 2023 - Word to the Wise
Expert view
Expert from Email Geeks explains that some email validation APIs use botnets, spammer tactics, or buy data from ESPs and that most of the industry is problematic at best.
30 Jul 2023 - Email Geeks
5 technical articles
To remove your IP from Microsoft's block list, use their delisting portal after resolving the underlying issues. Utilize email validation APIs like Mailgun to verify email addresses, reduce bounce rates, and improve sender reputation by checking syntax, disposable addresses, and MX records. Warm up your IP gradually by increasing email volume to establish a positive reputation. Leverage services like Amazon SES that automatically manage IP reputation and offer tools for monitoring sending metrics. Adhere to Google's bulk sender guidelines, including email authentication, maintaining a low spam complaint rate, and providing an easy unsubscribe option to improve deliverability and avoid being marked as spam.
Technical article
Documentation from Google Postmaster Tools explains that following their bulk sender guidelines can help improve your email deliverability and avoid being marked as spam. This includes authenticating your emails, maintaining a low spam complaint rate, and providing an easy unsubscribe option.
4 Jul 2021 - Google
Technical article
Documentation from Amazon SES explains that they automatically manage IP reputation and provide tools to monitor your sending metrics. If you encounter any deliverability issues, they offer resources and support to help you resolve them.
17 May 2025 - AWS
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