Group email being blocked

Question

Group email being blocked

Susan Minix 0

When trying to send email to a small group of 38 people, I'm getting the following message from Outlook.com, followed by a System Admin message saying the message is undeliverable.

The daily message limit helps us free the world from spammers--we're sorry that it's getting in your way.

Thanks

Susan Minix 0 Reputation points

2026-03-13T20:04:00.8366667+00:00

These are the only emails sent out today, so we are not anywhere near the maximum number. Within the past month I emailed all of the same contacts in a group message without a problem. I have been forced to email each person individually and those all worked. I need to have the block taken off the account.
Hornblower409 15,815 Reputation points

2026-03-14T10:44:40.67+00:00

If the Q&A Assist Answer did not solve your problem:

Click the [No] button on the "Was this answer helpful?" bar under the answer. If there is a [Reject] button visible, click that too. This should signal the forum moderators that you want a human to pick up this question.

If that does not get you a human response, type "Not Solved" in the "Add Comment" box below and then click the [Add Comment] button. I will try to offer some suggestions on what you can do next.
Susan Minix 0 Reputation points

2026-03-14T15:17:06.6033333+00:00

I keep getting the same AI message. I have not even come close to reaching the daily limits for email. I checked my microsoft cloud storage and have only used 1%, so that is not the problem. The account is not new, the recipients are known. In the past month I have sent email to the same group of people with no problem. I am getting an email from microsoft that the account is blocked and a undeliverable message from the system.
Hornblower409 15,815 Reputation points

2026-03-14T20:20:34.72+00:00
@Susan Minix said

I am getting an email from microsoft that the account is blocked and a undeliverable message from the system

Do I understand correctly - At first you were getting the "daily message limit" notification but that has changed to some kind of "account blocked" notification?

If so, this is not the kind of problem that lends itself to debugging via a forum and you probably need to bring in Microsoft Support so they can examine your tenant on the server.

In App Support - New Outlook for Windows or Outlook Web

From the main menu: Help -> ? Help

{This should open the Help side panel}

Search Help = {Your problem} and press Enter

Still need help? [Yes]

If you get "We're here to help": Tell us your problem = {Your problem} [Get Help]

[Sign In] {Use any Outlook/Microsoft account}

Choose a support option -> Chat with a support agent in your web browser
Susan Minix 0 Reputation points

2026-03-15T13:13:15.85+00:00

Thank you. I felt like I needed to get support from Microsoft all along especially when I kept getting the same answer over and over again. Really frustrating. The problem is the same as it was from the start. I have checked all of the things suggested as the issue and none of them of them are a problem. Just to test I sent a test email from another email address to the same group and that worked. So it is specifically an issue with this address. I have. It been able to find a way to get the support I need so I appreciate your instructions on how to do so. I will give that a try.
Susan Minix 0 Reputation points

2026-03-15T13:18:34.1133333+00:00

Unfortunately I am not getting the prompt "still need help"
Hornblower409 15,815 Reputation points

2026-03-15T16:46:19.5466667+00:00
@Susan Minix said

Unfortunately I am not getting the prompt "still need help"

Try getting to Chat Support via a browser

Open a browser to https://support.microsoft.com/en-us/home/contact

Tell us your problem: "message sending limits"

[Get Help] {Scroll down to the bottom of the page} [Sign in to Contact Support]

Sign in with any Microsoft account

Products and services: "Microsoft 365 and Office"

Category: "Outlook"

[Confirm]

Choose a support option -> "Chat with a support agent in your web browser"

1 answer

Your answer

Susan Minix 0 Reputation points

2026-03-13T20:04:00.8366667+00:00

These are the only emails sent out today, so we are not anywhere near the maximum number. Within the past month I emailed all of the same contacts in a group message without a problem. I have been forced to email each person individually and those all worked. I need to have the block taken off the account.
Hornblower409 15,815 Reputation points

2026-03-14T10:44:40.67+00:00

If the Q&A Assist Answer did not solve your problem:

Click the [No] button on the "Was this answer helpful?" bar under the answer. If there is a [Reject] button visible, click that too. This should signal the forum moderators that you want a human to pick up this question.

If that does not get you a human response, type "Not Solved" in the "Add Comment" box below and then click the [Add Comment] button. I will try to offer some suggestions on what you can do next.
Susan Minix 0 Reputation points

2026-03-14T15:17:06.6033333+00:00

I keep getting the same AI message. I have not even come close to reaching the daily limits for email. I checked my microsoft cloud storage and have only used 1%, so that is not the problem. The account is not new, the recipients are known. In the past month I have sent email to the same group of people with no problem. I am getting an email from microsoft that the account is blocked and a undeliverable message from the system.
Hornblower409 15,815 Reputation points

2026-03-14T20:20:34.72+00:00

@Susan Minix said

I am getting an email from microsoft that the account is blocked and a undeliverable message from the system

Do I understand correctly - At first you were getting the "daily message limit" notification but that has changed to some kind of "account blocked" notification?

If so, this is not the kind of problem that lends itself to debugging via a forum and you probably need to bring in Microsoft Support so they can examine your tenant on the server.

In App Support - New Outlook for Windows or Outlook Web

From the main menu: Help -> ? Help

{This should open the Help side panel}

Search Help = {Your problem} and press Enter

Still need help? [Yes]

If you get "We're here to help": Tell us your problem = {Your problem} [Get Help]

[Sign In] {Use any Outlook/Microsoft account}

Choose a support option -> Chat with a support agent in your web browser
Susan Minix 0 Reputation points

2026-03-15T13:13:15.85+00:00

Thank you. I felt like I needed to get support from Microsoft all along especially when I kept getting the same answer over and over again. Really frustrating. The problem is the same as it was from the start. I have checked all of the things suggested as the issue and none of them of them are a problem. Just to test I sent a test email from another email address to the same group and that worked. So it is specifically an issue with this address. I have. It been able to find a way to get the support I need so I appreciate your instructions on how to do so. I will give that a try.
Susan Minix 0 Reputation points

2026-03-15T13:18:34.1133333+00:00

Unfortunately I am not getting the prompt "still need help"
Hornblower409 15,815 Reputation points

2026-03-15T16:46:19.5466667+00:00

@Susan Minix said

Unfortunately I am not getting the prompt "still need help"

Try getting to Chat Support via a browser

Open a browser to https://support.microsoft.com/en-us/home/contact

Tell us your problem: "message sending limits"

[Get Help] {Scroll down to the bottom of the page} [Sign in to Contact Support]

Sign in with any Microsoft account

Products and services: "Microsoft 365 and Office"

Category: "Outlook"

[Confirm]

Choose a support option -> "Chat with a support agent in your web browser"

Answer 1

Outlook.com is enforcing its sending limits and is treating the group message as exceeding the daily quota designed to prevent spam.

Key points from the limits:

Outlook.com restricts how many recipients can be sent mail to per day and per message.
For Microsoft 365 subscribers, documented limits are:
- Up to 5,000 recipients per day
- Up to 500 recipients per message
- Up to 1,000 “non-relationship” recipients (people never emailed before) per day
For non‑subscribers or newer accounts, limits are lower and can vary based on usage history and reputation. New accounts start with a low sending quota that increases as credibility is established.

What this means for the scenario:

Even though only 38 recipients are in the group, the account may have:
- Hit its daily recipient limit (for example, after other messages sent the same day), or
- Hit the daily “non‑relationship recipient” limit if many of the 38 have never been emailed before, or
- Be under stricter limits because the account is new or has limited sending history.

Recommended actions:

Reduce volume temporarily
- Send to fewer recipients at a time and spread messages across multiple days.
- Prioritize recipients already emailed before to stay under the “non‑relationship” limit.
Build account reputation
- Use the account regularly over time with normal, low‑volume sending.
- Avoid sending the same or very similar content to many new recipients at once.
If the account is new
- Expect a lower temporary quota until the system increases it automatically as credibility is established.

If non‑delivery reports continue even with low volume and known contacts, use the guidance under “Can’t send mail in Outlook.com” and, if applicable, follow the link there to Sender Support in Outlook.com for further investigation.

References: