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SMTP Error 0x800CCC60

Last modified: October 1, 2022
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SMTP Error 0x800CCC60


The SMTP server returned an error –>

Account: ‘accountname’,
Server: ‘’,
Protocol: SMTP,
Server Response: ‘rblsmtpd: pid 11559: 451 Blocklist Removal Center‘,
Port: 25, Secure(SSL): No,
Error Number: 0x800CCC60

Root Cause:

Your server is as of now under ‘OPEN RELAY’. This implies your server being utilized by spammers to convey spam messages.

How to Fix Outlook SMTP Error 0x800CCC60

Method 1- Check Account Settings

  1. Firstly, open Outlook and go to the Tools menu or file tab.
  2. Select Account Settings and open email.
  3. Next, double click on account and click on More Settings.
  4. Check and verify your email and password.
  5. After that, make sure to enable the authentication while sending email. 
  6. Lastly, verify the port number is correct ( set to 25 or 587).

Method 2- Disable Firewall

  1. Firstly, open the firewall that installed on your PC.
  2. Secondly, select Advanced settings in Control Panel and check whether Outlook is blocked or not. If Outlook is blocked, then unblocks it.

Method 3- Check Blacklist IPS

  1. Firstly, log into whatismyipaddress and check your IP address.
  2. Then, open the firewall and check the blocked column of your IP address.
  3. If your IP is in blacklist, remove them and then Save the Setting.
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