# 5.7.708 Bounce: Traffic Not Accepted From This IP

URL: https://email-validation.org/bounce-codes/5-7-708/
Updated: 2026-11-06

> Documentation index: https://email-validation.org/llms.txt

**At a glance**

- **Type:** permanent failure (class 5, RFC 3463 §2). The sending server does not retry; sending the same message again fails the same way until the cause is fixed.
- **Basic code:** varies; the enhanced code is the part that identifies the problem.
- **Enhanced code 5.7.708:** not in the IANA registry; the group is security or policy status (RFC 3463 §3.8).
- **Who uses it:** Microsoft (Exchange Online): access denied, tenant has exceeded threshold (5.7.705) or traffic not accepted from this IP (5.7.708).

A 5.7.708 bounce from Microsoft 365 means Microsoft is not accepting mail from your tenant's sending IP, because most of the mail your Microsoft 365 organization sent recently looked suspicious. The block covers the whole tenant, not one user.

## What it means

This is Microsoft's code, not one from the IANA registry. Microsoft's [Exchange Online NDR reference](https://learn.microsoft.com/en-us/troubleshoot/exchange/email-delivery/ndr/non-delivery-reports-in-exchange-online) lists two codes for this:

- **5.7.705:** access denied, the tenant has exceeded its threshold.
- **5.7.708:** access denied, traffic not accepted from this IP.

Both mean that a large share of your tenant's outgoing mail was judged suspicious, and Microsoft restricted the tenant's sending. Microsoft notes this is often caused by compromised accounts, and often seen with new tenants.

The block is different from a single account being stopped. One mailbox blocked for sending spam gets [5.1.8](https://email-validation.org/bounce-codes/5-1-8/). An IP banned at the receiving side gets [5.7.606](https://email-validation.org/bounce-codes/5-7-606/).

## Common causes

- One or more accounts were taken over and used to send spam or phishing.
- A new tenant started sending large volumes straight away.
- An application or script sends bulk mail through Microsoft 365 that recipients do not want.
- A tenant created mainly to send mass mail.

## How to fix it

1. Check every account for signs of compromise: unexpected sign-ins, new inbox rules or forwarding (see [5.7.520](https://email-validation.org/bounce-codes/5-7-520/)), and sent items the user did not write. Reset passwords and require multifactor sign-in where it is missing.
2. Look in the admin center for users restricted from sending, and for alerts about suspicious outbound mail.
3. Stop any bulk or marketing mail going through the tenant until the cause is clear.
4. Check that the domains you send from are added and verified in the tenant; unverified domains can bring [5.7.750](https://email-validation.org/bounce-codes/5-7-750/).
5. Contact Microsoft support to ask for the restriction to be lifted.
6. Afterwards, send bulk mail through a service built for it, and keep Microsoft 365 for person-to-person mail.

## What to do with the address

Keep it. The block is about your tenant's sending, not about the recipient.

## Related codes

- [5.7.606](https://email-validation.org/bounce-codes/5-7-606/): Banned sending IP (Microsoft)
- [5.7.750](https://email-validation.org/bounce-codes/5-7-750/): Blocked from sending from unregistered domains (Microsoft 365)
- [5.1.8](https://email-validation.org/bounce-codes/5-1-8/): The sender's domain is refused

See [every bounce code](https://email-validation.org/bounce-codes/) in the dictionary.

Many bounces from addresses that do not exist can be avoided: check an address with our [free email checker](https://email-validation.org/email-checker/), or [clean a whole list](https://email-validation.org/bulk-email-verification/) before you send.