Can't send emails from my outlook/hotmail account on Windows

The error 550 5.7.501 Service unavailable. Spam abuse detected from IP range. AS(130) means the outgoing connection used by the Windows desktop is being blocked as spam by Outlook.com’s protection systems. Because sending from Android and iPad still works, the Hotmail account itself is valid; the issue is with how mail is being sent from the Windows environment.

Use these steps that are supported in the provided guidance:

1. Check for large or problematic messages
   • In classic Outlook (or New Outlook), open the Outbox and Sent Items.
   • Delete any messages with large attachments (over ~20–25 MB) or many recipients, then try sending a simple text-only message to a single recipient.
   • Large or repeated sends can contribute to spam-like behavior.
   • For attachment limits and behavior, see the guidance under “Do your messages contain large attachments?”
2. Verify the account and connection in Outlook
   • Make sure Outlook is actually connected to the server:
     • Look at the status bar for Disconnected, Working Offline, or Trying to connect…
     • If shown, go to Send/Receive tab → select Work Offline once to return to online mode, then try Send/Receive again.
   • Confirm that other internet access (e.g., browsing to microsoft.com or bing.com) works from the same PC.
3. Check antivirus email scanning
   • Some antivirus products scan outgoing email and can interfere with sending or cause patterns that look like spam.
   • In the antivirus settings, look for options like Internet Email Auto Protect or Internet Email Protection and temporarily disable them.
   • After disabling, send a small test message to the same recipient.
4. Improve spam reputation signals from the Outlook.com side
   • From the Outlook.com web interface:
     • Add a clear display name to the account so the “From” field is easily identifiable.
     • Add frequent recipients to Contacts.
     • Send an email to the Hotmail address itself, open it, and reply to it.
   • These actions are recommended to improve spam reputation when Outlook.com is involved in delivery.
5. If non‑delivery continues for correct addresses
   • When a non‑delivery report (NDR) is received and the recipient address is confirmed correct, the guidance is to follow the Outlook.com sender support steps.
   • The NDR itself usually includes a reason such as spam filtering; in this case, the 5.7.501 spam/abuse code confirms that.
6. If the error mentions blacklists or blocking
   • For errors that include terms like blocked, listed in, or references to blacklist services (Spamhaus, Spamcop, etc.), the recommendation is to contact the recipient’s email provider and request unblocking.
   • In this scenario, the block is on the IP range used by the desktop’s connection; if it persists across recipients, contacting Outlook.com/Microsoft support from the account’s web interface is typically required so they can review and adjust the spam reputation for that IP range.
7. As a temporary workaround
   • Until the IP‑range block is cleared, continue sending from Android or iPad (which use different outbound paths) or from the Outlook.com web interface in a browser, where sending is not blocked.

If, after these steps, every message from the Windows desktop still generates the same 5.7.501 NDR to multiple different recipients, the remaining action is to work with Microsoft/Outlook.com support so they can investigate and remove the spam block on the affected IP range.

References:

• Can't send or receive email in Outlook.com
• Sender Support in Outlook.com
• Sent email in Outlook.com comes back "delivery failed"
• I can't send or receive messages in Outlook