Location is not mountable

I'm trying to setup Deja-Dup for making backups to a remote host, but I keep encoutering on the following Error: Backup Failed: Location is not mountable.

The following I've tried:
- Test if I can actually use sftp to connect to my remote host, which works fine.
- Test with an account that doesn't use a SSH-Key for obtaining access to my remote host, which doesn't change the outcome.
- Test if I can make a backup locally, which works fine.

I've tried creating a log file, but it stays empty.

I'm using the following systems:
Client: Xubuntu 11.10 x86 Running on a Virtual Box instance which itself is running on Windows 7 x86_64
Server: Ubuntu 11.10 Server x86_64 Which is running as a VPS

Hope I've put enough information in it, if you need more, please let me know.

Hope you can help.