Xubuntu 17.10 was mostly a maintenance release in which the migration of Xfce to GTK3 was prepared.
This release has reached End of Life
The downloads are listed here only for archival purposes. Running this release is not recommended under any circumstances.
I understand and accept the risks
The above link will redirect you to old-releases.ubuntu.com, where you will have to navigate to the correct release manually. You have been warned.