File Transfer Protocol (FTP) is a great way to share files and directories.

With additional options to transfer large files, resume from failed transfer, scheduled uploads etc. FTP is quite popular. But at times, these transfer may not work correctly.

Then ftp server shows various responses and “331 password required for ftp” is one among them.

At Bobcares, we help website owners to fix FTP related errors as part of our Outsourced Technical Support for web hosts.

Today, let’s see more on the response code “331 password required for ftp“.

 

What is “331 password required for ftp” ?

In FTP, we normally transfer files using ftp clients such as FileZilla, CuteFTP, Serv-U etc.

Fortunately, the ftp server provides many interim messages while making connection between the computer and the server. All these messages contain an integer code in it.

In our code, the value is 331.

The 3xx range of code is a Positive Intermediate Reply. This means that the command was successful, but the server needs additional information from the client to complete processing the request.

The second digit as in “x3x” refers to authentication and accounting. They contain the replies for the login process and accounting procedures.

The third digit in the FTP server code gives further explanation on what exactly is causing this code.

In a nutshell, 331 error indicates that your ftp username is accepted by the server and now you need to provide a password.

 

Where we see “331 password required for ftp” ?

We normally see this status code after the ftp client sends a user name, regardless of whether the user name that is provided is a valid account on the system.

With our expertise in managing servers, we often we see this response from FTP in many ftp clients.

A typical response in FileZilla looks like :

Status: Resolving address of example.com
Status: Connecting to 192.168.xx.xx...
Status: Connection established, waiting for welcome message...
Status: Initializing TLS...
Status: Verifying certificate...
Status: TLS connection established.
Command: USER bob
Response: 331 Password required for bob
Command: PASS ****
Response: 530 Login or password incorrect!
Error: Critical error: Could not connect to server

Here, the response from the Filezilla is “PASS” where it provides the password of the ftp user “bob”.

This means that, for the FTP server response “331 password required”, all ftp clients need to reply back with the password of the ftp user.

 

How to solve issues with “331 password required for ftp” ?

Immediately, after the ftp response “331 password required”, ftp connection can break abruptly because of bad username and password combinations. And again this happens mainly due to two reasons.

 

1. Bad user name

The 331 ftp response is shown regardless of whether the user name that is provided is a valid account on the system. That is, by default ftp server accepts any given username.

The exact check is done when the password is supplied. And when there is a mismatch, ftp connection shows errors.

Recently, in a cPanel server, customer had problems connecting as ftp user. In cPanel, additional ftp accounts has the format of username@domainname. But customer was using only username without the “@domainname” part to connect.

To fix, our Support Engineers additionally verified the username and updated customer on the correct format of username.

 

2. Bad password

Similarly, ftp errors can happen with password problems as well. The typical cases here would be:

1. Incorrect typing of password
2. Empty password
3. Using old password.

The simple solution here is to reset the ftp account password. And with the new password, ftp connection works fine.

Additionally, ftp errors can also occur due to connectivity issues to the ftp server. In such cases, our Support Engineers look for IP address block on server firewall, network connectivity issues from the customer side, Antivirus installed on customer’s personal workstation etc.

 

Conclusion

We normally see the status code “331 password required” after the ftp client sends a user name. Today, we’ve discussed on the scenarios where this response shows up. Also we saw typical errors related to this and how our Support Engineers fix them.