If you’re using Filezilla to ftp into a server, you likely already know it’s important to make sure you’re using the right host, un, and pw.

But here’s something I didn’t know to look for that gave me some grief this a.m. and I didn’t find it on any forums.

One of  my clients uses Bluehost to host multiple websites. He’s taking advantage of Bluehost’s super deal of letting you host as many sites as you like for a few dollars a month. However, when you host using that method, you must choose one main site, and all your other sites are actually sub-domains.

So, for example, if your main Bluehost site is mydomain.com, any other site you put up is going to be a sub-domain. So let’s say you put up a new site on your domain name of fluffybigbunny.com

You can verify if it’s a sub-domain by going to fluffybigbunny.mydomain.com or mydomain.com/fluffybigbunny.com

Okay, you may already know this happens if you’re accustomed to using Bluehost.

But here’s what I didn’t know. When creating an ftp account, go ahead and create it as you usually would, but whereas normally if you created [email protected] as your un, normally in Filezilla (or other ftp clients) you can just put jobunny as your un. This will result in a failed login attempt.

Even though you’ve already put mydomain.com as your host, you must then put [email protected] as the username, not just jobunny. I suspect this is due to the sub-domain nature of how things are set up on this type of Bluehost server.

So, if you’re getting this error message: filezilla 530 login authentication failed critical error maybe this post will save you a little time, trouble, and the urge to beat your head against a wall.