Tom, it is because you've not told Xara anything about your https:// access in the same way you didn't know about having an http:// site.

I'm afraid it will be up to you changing server settings and reading into what your server provides.
There will be a file named .htaccess that needs to be altered.
Your potentially have to address calls http:// to https://, ...://www.xyz.net to ...://xyz.net and even redirect calls to index.html to index.htm.
These are nothing to do with Xara.

When you have this sorted, you can probably alter your FTP call to use https.

Acorn