The Directory is already being used by another IIS web site

Hi, I am running into an error when creating new Sharepoint 2010 web applications:

The directory
C:\inetpub\wwwroot\wss\VirtualDirectories\sk-test1.**.***.**443 is already being
used by another IIS Web Site.  Choose a different root directory for your new
Web application.

I have searched the topic endlessly and I am still unable to find a solution. I get this error when I create a new Sharepoint Web application. I seems to have just started, I have already created 35 or so web applications before this without issue and now it won't let me create anymore for some reason... if I delete some of the Web Apps i created before it starts working again, but eventually I come across this error again.

I have checked to ensure that all web applications have a host header in them. The web applications are running on port 443. I have also tried creating the application on a different port, without luck. Creating a new folder for the web applications at this location:C:\inetpub\wwwroot\wss\VirtualDirectories2 works, but only one site can be made then it gives the error again.

You have my thanks for any help with this.