FTP errors are annoying as usual.

You want to upload an important file to your website using an FTP client, but it suddenly throws an error. Quite frustrating, sure.

One of these FTP errors is “530 valid hostname is expected“.

At Bobcares, we help server owners resolve such errors as part of our Dedicated Support Services for web hosts.

Today, we’ll discuss the top 2 reasons for this error and how we fix them.

FTP error “530 valid hostname is expected” – Brief explanation

FTP error 530 valid hostname is expected is a common error seen on FTP servers hosted on Windows system. This error occurs when users set up IIS with multiple FTP sites.

So, every time users enter the correct username and password, the system still prompts this error.

FTP error “530 valid hostname is expected” – Causes and Fixes

We now have a basic understanding of this error. Let’s now see the main reasons for this error and how our Dedicated Support Engineers fix them.

1) Incorrect binding in IIS

FTP binding is the combination of IP address, port and virtual hostname. The FTP server uses these details to listen to the requests made to that FTP host. So, wrong binding settings for the website can always break the FTP connection to the server.

We’ve seen many instances where users try to connect to the FTP site using a hostname that’s not configured in the IIS bindings. As a result, the FTP server was unable to identify the FTP host that connects to the server and throws the FTP error 530 valid hostname is expected.

Similarly, another common mistake we see is that customers set up the FTP site to bind to the localhost loopback IP address(127.0.0.1). As a result, the hostname can’t be resolved externally and the connection can be dropped.

How we fix?

Firstly, our Hosting Engineers get the FTP login details from the customer. Further, we check the Binding settings of the domain on the server. If the FTP host is not configured in the bindings, we’ll add the correct binding for that hostname in the IIS settings.

In addition to that, we confirm the IP address specified in the binding configuration is a non loop back address. That is, it should be the server’s public IP address or server’s internal IP address depending on how the server is configured.

[Need a Server Expert to look into your IIS binding settings? Click here, our Server Administrators are online 24/7.]

2) Incorrect username in the FTP client

This error commonly happens when users configure multiple FTP sites on the same IP address. In other words, multiple websites have same the set of IP address, Port number, etc. So, the FTP server can’t determine the exact account for which the user give the FTP credentials.

As a result it throws the FTP error 530 valid hostname is expected.

How we fix?

It’s a usual case that customers need to host multiple domains on the same IP address. So, here our Support Engineers suggest customers use a hostname and user combination in the format ‘hostname|user'(the symbol | separates hostname and user) in the username field of the FTP clients like Filezilla.

For example, consider that a user wants to connect to the FTP host ftp.domain.com with the username testing. Then, you should give the username as ftp.domain.com|testing. Here, the FTP server can easily identify that the FTP client is connecting to the host ftp.domain.com with the username testing.

[And, do you need a Server Expert to look into this error? One of our Support Engineers can fix it for you.]

Conclusion

In short, FTP error 530 valid hostname is expected can occur due to incorrect binding in IIS or wrong username given in the FTP client. Today, we’ve discussed these causes in detail and how our Support Engineers fix these problems.