Troubleshooting Microsoft Emails Going to Spam in 2024

Microsoft recently changed its email-sending policies and a lot of users are facing high bounces, and low open and reply rates. Most of the users aren’t able to troubleshoot the same since the old techniques aren’t working anymore. This has something to do with overall infrastructure and adapting to bulletproof deliverability set up.

What is causing the spam issue?

The issue is being caused by recent changes MSFT made to stop spam, Since a lot of users were shifting from Google to Microsoft inboxes due to ease of set up and new policies from google. This caused a lot of spam going out from MSFT inboxes which is why all of a sudden new measures were brought.

Does that mean every inbox is affected?

No, some users are still performing well while most are affected. The new changes have a direct impact on your infrastructure and sending policies. A vulnerable infrastructure can break down at any time from 80% open rates to 10% open rates it can impact your clients and overall performance but don’t worry we have a working solution for that which we are going to discuss step by step below.

Troubleshooting email deliverability step by step

Please note, that this has to be carried out step by step since the causes can be different and we don’t want to jump to step 4 right away as it won’t help!

Step 1: Rotating the IPs

Understanding how IPs play a significant role in your email deliverability is a must, your sender IP determines 70% of your deliverability. It’s a key identifier for ISPs to determine if your mail should be landing in spam or primary inbox. If you’re facing an issue the first step is to rotate your IP.

You can rotate your IP by reaching out to Microsoft support and asking them to rotate the IP and allocate a good reputed IP, this can change the game for you.

Step 2: Shifting to bulletproof deliverability infrastructure

If one mailbox is affected it can hamper the deliverability of other mailboxes in that tenant. We noticed a lot of users have multiple inboxes and domains on the same tenant which means the entire domains and mailboxes in a single workspace is affected.

Bulletproof email deliverability infrastructure:

This infrastructure has almost 100% guarantee of deliverability, we have been using it for our clients for over 3 years and we have never been in trouble.

1) One workspace with 3 mailboxes only

If you have like 10 domains with 20 mailboxes on one workspace you are letting each one of them vulnerable. Instead having 3 mailboxes one a single workspace means if one email is affected it won’t hamper major of the emails. You can easily replace a single workspace. It also makes it safe for mailboxes since a single workspace won’t be sending plenty of emails.

2) Using RDPs to log in to your mailboxes

RDPs or Remote Desktops with IPs are a great way to keep your mailboxes logged in from a single IP. Image your mailbox has no login and you’re sending over 30 emails per day. Would it not flag the mailbox? yes, of course, it would. You should also think about having multiple mailboxes created or logged in from a single IP address how bad is that? Hence if your mailboxes are logged in from a single IP and stay logged in while you’re doing a campaign it would make it very easy for you.

3) Strategic warmup and slow ramp, not just 2 weeks

I talked about strategic warmups in my other blog, most people warm up for like 2 weeks and start sending 30-50 emails a day. Image a normal human being who never does this. No one does 50 emails every day after 2 weeks which makes a pattern major of cold emails out there doing the same and ESPs are well aware of patterns. I would suggest going through the blog hyperlinked above to save yourself and your mailboxes.

4) Frequent change of copies including subject lines, big yes to spintax.

We also noticed a lot of users aren’t changing the copies even though they are doing the spintax which is a big factor of making yourself vulnerable to spam. Your copies should be changed every 2 weeks now vs how it was before and yes Spintax plays a major role.

5) Matching country mailboxes.

You know it is less likely that an Indian mailbox will interact a lot with US mailboxes subject that they are internal mailboxes which a lot of MNCs use. Usually, there would be a lot of security checks on such emails that are going cross country as to avoid scams, hacks, or information leaks.
In order to make your outbound effective you would want to use US Mailboxes in the US and Indian mailboxes in the US, which also applies to other countries.

6) Different credit cards and phone numbers

BE CAUTIOUS! While purchasing your mailboxes, using a credit card and phone number which was earlier used across multiple mailboxes or spam mailboxes is a big hint for ESPs to block you or flag you. You can use multiple tools like Smspool or Virtual credit card providers based on your home country to tackle these factors.

7) Mix of providers ( Google, MSFT, Zoho etc)

Using a mix of providers is a great idea always as it would keep you safe if a single provider is affected but make sure to test the providers before as it depends on different locations for the US a Google or a Microsoft account is good but not Zoho but for the Indian market, Zoho emails are performing well.


While we understand deliverability is very important we need to understand the sending tool is as important, tools like Smartlead or Instantly offer rotating IPs from your campaign level which boosts deliverability. In addition to that keep in mind the human-based sending behaviors the closer you can get to a human-based sending the better your deliverability. Stay tuned for more information or reach out to the Click Suggest team for any advice.

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