I CAN'T SEND E-MAILS

Question

i can't send e-mails. the problems appear to all the e-mails ending at : david-energy.co.il

can you help me please ?

Answer 1

Hi,

Thank you for sharing your question. I understand how disruptive it can be when messages to a specific domain suddenly fail, especially when all your other email traffic works normally.

Based on guidance from Microsoft Learn discussions, issues like this often occur when the receiving domain is being blocked by an anti‑spam policy, when the destination server can’t validate the address, or when DNS records such as MX, SPF, or DKIM are misconfigured either on your side or the recipient’s side. Microsoft notes that errors related to recipient lookup failures are frequently tied to anti‑spam policies or domain‑handling issues, and reviewing those configurations is an important first step.

In many cases where email fails only for one domain, the root cause is DNS‑related, such as incorrect or missing MX or SPF records on the receiving side, which aligns with common troubleshooting recommendations for domain‑specific delivery failures. To move toward a resolution, I recommend checking whether you receive any bounce‑back or Non‑Delivery Report (NDR) codes, reviewing your organization’s anti‑spam and outbound policies in the Exchange admin center, and confirming that the receiving domain’s DNS records are valid and responding as expected. If the issue persists, message tracing in the Exchange admin center can help identify at what point the message is being rejected.

May I ask if you are receiving a specific error code or NDR when sending to david-energy.co.il, and whether these messages fail from all devices and mail apps, including Outlook on the web? Please feel free to share any additional details, and I’ll be glad to help you continue narrowing this down and get your mail flowing properly again.

 

 I hope this helps.

 

Best Regards,

Noel

Answer 2

For messages to a specific domain (such as addresses ending in @david-energy.co.il), common causes are:

1. The recipient server is rejecting or blocking the messages.
2. The address is invalid or the recipient mailbox is full.
3. The message is being blocked by spam or security filters.

Take these steps:

1. Check any Non-Delivery Report (NDR)
   • When sending fails, look for a bounce/undeliverable message in the Inbox.
   • Open it and review the error text. Typical reasons include:
     • Invalid email address
     • Mailbox full
     • Server issues on the recipient side
     • Spam filter blocking the message
   • The NDR usually explains why the message to that domain is not accepted.
2. Confirm the recipient address and mailbox
   • Make sure each @david-energy.co.il address is spelled correctly.
   • Ask one of the recipients to confirm that the mailbox exists and is not full.
3. Ask recipients to add the sender to Safe Senders
   • Ask someone at david-energy.co.il to add the sending address to their safe senders/allow list in their email system. This helps if their spam filters are blocking the messages.
4. Check sending limits and reputation
   • If the account is new or sending many messages, sending limits or reputation controls may temporarily restrict delivery. See Sending limits in Outlook.com.
5. If there is a non-delivery receipt but the address is correct
   • Follow the guidance in Sender Support in Outlook.com to investigate why messages are being rejected.

If the NDR shows a specific SMTP error like 550/553/relay prohibited, this usually indicates a policy or anti-spoofing rule on the recipient or ISP side, and their mail administrator must adjust their settings to allow messages from the sending service.

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References:

• Can't send or receive email in Outlook.com
• I receive a 550, 553, or relay-prohibited error when sending email messages