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Various Reasons for IP Address Block in CSF

By any chance, if you get access denied when accessing cPanel account, do not try to login multiple time at that situation! If you are using wrong login credentials to access the cPanel and you have already tried 10 or 20 times in 5 minutes, then by that time your public IP will be blocked in the CSF firewall. So before trying to login to your cPanel account, you have to make sure that the Login credentials are correct.

Block due to failed POP3/IMAP login attempts

If you are seeing the error windows of IMAP/POP3 failed authentication in your email client, then most probably the login credentials you are currently using for the email account are outdated/incorrect. In this case, also you will end up with your IP get blocked in the CSF as the email client will not stop trying to access the mail server with that wrong credentials.


Block due to failed SMTP login attempts

Another way is that in any case if the SMTP authentication gets invalid so that you are unable to send email from the email client. So it is important to take care of the SMTP credentials to login, make sure that you are using the full email address and the correct password.


Incorrect email client settings

In some cases, the email client settings also cause for an IP block.

Failed FTP/SSH login
If you are accessing the server via FTP with some FTP client, then make sure that you are using the correct login details with the FTP client. Also if you are using incorrect port number to log in then also your IP get blocked in the firewall.

Failed web page login
In some cases, if the website needs authentication to further check as the website has some type of protected directory. Please make sure you use correct login details in the authentication box. Otherwise, there is a chance for your IP get blocked.

The most common reason to get blocked is failed IMAP/POP3 login attempts, we’ve shared a few steps on what you can do to avoid getting blocked.

1) Modify the email account password and include the same password in email client
2) Enable “My outgoing mail server (SMTP) requires Authentication’ option in the Email client
3)Please make sure your server time outs is set to 3 minutes, you can do that by following the steps listed below.
Go to your account settings in Mail client click on More settings > Advanced and set the server time outs to 3 minutes.

You can verify the email account login using the Webmail, you can access webmail, by putting the subdomain webmail in front of your domain such as webmail.yourdomain.com (make sure to replace yourdomain.com with your actual domain)

4. Ensure you are using correct username and password.
5. Please note that the password field is case-sensitive, so make sure you’re using the correct capitalization and check to see if Caps Lock is on
6.Please ensure that space is not appended with the password.
7.Could you please check if all your devices have the settings for the mail up to date, any old(unused) device could be trying to login with the wrong login details resulting your IP address getting blocked by our firewall.


Need help managing your server? Getoutsourced has a team which currently manages servers for multiple companies.

Contact us and set an appointment, so one of our team members will get back to you and discus all the details. 

Not convinced? Check out why Getoutsourced.


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