Fix Eudora authentication failed error with these simple solutions

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Updated onOctober 4, 2023

updated onOctober 4, 2023

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Many users still use Eudora as theiremail client, but many reportedEudora authentication failederror. We have already sharedcommon problems and fixes for Eudora, but in this article, we take a look at the possible solutions to fix the Eudora authentication failed/requirederror.

How can I fix Eudora authentication failed error?

1. Set the correct SMTP port

One of the common causes ofEudora authentication failederroris caused by an incorrect port configuration forSMTP. Find the correct port for your network provider and then proceed with the steps below.

Next, you need to modify thedeudora.ini fileand disableCRAM-MD5. Here is how to do it.

2. Use alternative port

If you’re still havingEudora authentication failederror, try a different combination of ports that are available for your email server.

3. Diagnose port blocking

If a security program installed on your computer is blocking the ports from creating a connection with the mail server, then disabling the security programs such as firewall and antivirus can do the trick.

However, to know if the program is blocking the ports, you can start the terminal and run telnet.

If you don’t see the message, follow the next solution to disable security programs on your computer.

Note:Telnet might be disabled by default on the newer version of Windows, including Windows 10.

If you getTelnet is not recognized as an internal or external commandmessage here is how to enable Telnet on Windows 7 and above PCs.

4. Disable firewall

If you have an antivirus with an activefirewallinstalled, it can causeEudora authentication failederror. One way to troubleshoot compatibility issues it to turn off thefirewalltemporarily.

If you don’t have antivirus firewall activated, turn off Windows Defender Firewall. Here is how to do it.

Launch Eudora again and try to send an email. If the issue is still there, move to the next solution.

5. Disable antivirus

The antivirus program may incorrectly block genuine connections on your computer due to suspicious activity.

If you have an antivirus program installed, try to disable the antivirus for a limited time. Most of the antivirus allows you to turn off the protection for an hour or more. In case your antivirus is the problem, perhaps you should consider switching toBitdefender.

This antivirus offers great protection, and it won’t interfere with your system in any way, so be sure to try it out.

Eudora is still one of the most popularemail clientsamong its users, but the lack of development means the problems can remain unsolved for years. Nevertheless, we hope you fixed theEudora authentication failederrorusing our solutions.

Fix Eudora authentication failed error with these simple solutions#

How can I fix Eudora authentication failed error?#

1. Set the correct SMTP port#

2. Use alternative port#

3. Diagnose port blocking#

4. Disable firewall#

5. Disable antivirus#