I'm on a Windows VPS -

I'm trying to setup a new development site as a subdomain -- dev1.xxxxx.com as a host header based site so I don't have to allocate a new IP.

I have the FTP server setup in IIS and mapped to a new directory on my C/ drive. I have the host header correctly setup in IIS and have the FTP setup under a different port number since dev1.xxxxx.com and xxxxx.com share the same IP

What I'm having trouble with are the DNS settings - If I setup a new A record of dev1 for xxxxx.com - when I connect via FTP it's dumping me into the directory for xxxxx.com not the new dev1.xxxxx.com I setup.

I'm missing something fundamental and I'm sure obvious - I just don't have much experience with host header based sites as I always setup new sites with their own IP

From what I understand, Microsoft FTP only supports one domain. You should consider filezilla or ServU-FTP. I use Serv-U FTP on my VPS, and I have multiple domains configured and it works great. It is far more flexible than Microsoft FTP, and very easy to configure.

I know that doesn't answer your question, but it's been a long time since I've worked with the Microsoft FTP service. Even then, I've only ever setup Microsoft FTP with one website with Isolation.

Stay away from Windows built-in FTP. You can only support one logical FTP site per IP:port number. FileZila is free and much more flexible, you should definitely download and use that.

I agree with Mr. Raybould, you should stay away from windows FTP. Though, I must say that it's possible to accomplish this with user isolation if you require it.