# When an email is not delivered: why, and what to do

> In SkedX CRM, when an email sent from a connected Gmail or Outlook mailbox comes back (a bounce, or a "non-delivery report"), the email itself is marked Not delivered: a red band on top of the email in its conversation, a Not delivered line in the record's Notes & Activity, a red mark in the Inbox, and a bell notification to the person who sent it. The band says why in plain words and offers one action. Your address was blocked: the provider (for Microsoft 365, error 550 5.1.8 "bad outbound sender") has stopped your mailbox from sending any email, usually after many emails in a short time, many to addresses that do not exist, or a stolen password; nothing is wrong with the customer's address and the CRM keeps emailing it. Copy the fix for your admin copies the three steps (pause bulk sending, unblock the address in security.microsoft.com → Email & collaboration → Review → Restricted entities, change the password and turn on multi-factor sign-in); it is copied, not sent, because the blocked mailbox cannot send. The address does not exist: Send to another address, and the CRM will not email that address again. Their inbox is full: Send again later. Their server refused it: Send to another address, or call or WhatsApp them. Anything else: Write again. The server's own words are shown small for your IT person.

Product: SkedX CRM · Topic: Inbox · Draft — steps not yet re-verified in the live product

An email that never arrived used to look exactly like one that did. Now it says so, says why, and gives you the one next step.

## Step 1: See that it was not delivered

Open the record. In **Notes & Activity** the email shows the reason and **Not delivered**, and the person who sent it also gets a bell notification. Click the line to open the email.
Open it directly: https://crm.skode.ai/leads

## Step 2: Read why

The email opens with a red band on top: **Not delivered** and why, in plain words, and one button. The email you wrote stays readable underneath. The small line at the bottom is the server's own words — for your IT person, not for you.

## Step 3: Your address was blocked from sending

If the band says your provider **has stopped** your address from sending, the problem is your mailbox, not the customer: every email from it is coming back. Press **Copy the fix for your admin** and paste it to whoever looks after your email — it is copied, not sent, because the blocked mailbox cannot send. For Microsoft 365 the admin: **1.** pauses any bulk or automatic sending from that address (campaign or mail-merge tools); **2.** opens security.microsoft.com -> **Email & collaboration** -> **Review** -> **Restricted entities**, finds the address and chooses **Unblock**; **3.** changes its password and turns on multi-factor sign-in. It can take up to an hour. **How to fix this** opens this step.

## Step 4: The address does not exist

The band says the address **doesn’t exist**. Check it with the person, then **Send to another address**. The CRM will not email the address that bounced again, so a typo is not tried twice.

## Step 5: Their inbox is full

The band says **Their inbox is full**. It usually clears in a day; press **Send again** later. The address is still good, so the CRM keeps emailing it.

## Step 6: Their server refused it

The band says **Their email server refused it** — often a company filter. Press **Send to another address**, or call or WhatsApp them from the record.

## Step 7: Anything else

When the report gives no clear reason, the band says **This email came back undelivered** and offers **Write again**.

## Common questions

### Did SkedX get my address blocked?

No. SkedX sends each email the normal way through your own Gmail or Outlook, one at a time. Providers block an address for its own sending — many emails in a short time, many to addresses that do not exist, or a stolen password. Only your email admin can unblock it.

### I can still sign in and receive email — is it really blocked?

Yes. The block stops sending only; signing in and receiving look normal. In Microsoft 365 it shows in one place, **Restricted entities**, and Microsoft emails the alert to your admin, not to you.

### Will SkedX stop emailing the customer?

Only when their address does not exist. When your address was blocked, or their inbox was full, their address is fine and the CRM keeps it.

### Does this work for Gmail too?

Yes — any bounce that comes back to a connected Gmail or Outlook mailbox. The steps for your admin differ by provider; the band names yours.

### Old emails that bounced before this still say Sent

The CRM marks an email when its bounce report arrives after this change. Emails that bounced earlier keep the status they had.

Videos and screenshots © 2026 SkedX, with sample data only. Share and link to them freely; copying the SkedX product or its design is not allowed. Terms: https://skode.ai/terms/

## Related guides
- Set up your Inbox in SkedX CRM: channels, who becomes a record, the side panel, templates: https://skode.ai/help/crm/inbox/connect-your-inbox-in-skode-crm/
- Reading a profile page: https://skode.ai/help/crm/profiles/the-profile-page/
- What your clients and outside people receive from SkedX by email: https://skode.ai/help/crm/emails/what-your-clients-receive-by-email/

Source: https://skode.ai/help/crm/inbox/when-an-email-is-not-delivered/