[ubuntu] Authentication is required to start rpc-statd.service

I use my laptop as my NFS server and my desktop as an NFS client. I recently upgraded the desktop to Ubuntu 16.04 (it was on Ubuntu 14.04 before). The laptop/server is on Ubuntu 14.04, and I didn't' change anything on it. For some reason, after the upgrade, I had to comment out the only active line in /etc/hosts.deny on the laptop/server to get my NFS share to mount:

/etc/hosts.allow contains references to all the network adapters on my desktop.

After doing that, I'm able to mount the NFS share on the laptop/server on my desktop, but strangely, I'm prompted to authenticate with this message:

I enter the root password for the desktop (OK, to be honest I think it's the root password for the desktop, but the root password is the same on both computers) and my NFS share mounts.

I'd love to be able to fix both these problems, especially the problem with having to authenticate to get my NFS share to mount. Does anyone have any ideas?