[xubuntu] Installed XUbuntu, ran Boot Repair, still cant boot

Installed Xubuntu but couldn't boot into it, so ran Boot Repair. Previously had Ubuntu but installed over it. This machine is a XUbuntu only machine. I initially get a "No bootable device found" message but if I hit 'Enter' key, it brings up the old ubuntu grub menu. I think I found the problem in the Boot Repair log.
Boot Info Script e7fc706 + Boot-Repair extra info [Boot-Info 9Feb2015]

============================= Boot Info Summary: ===============================

=> Grub2 (v1.99-2.00) is installed in the MBR of /dev/sda and looks at sector
38228 of the same hard drive for core.img, but core.img can not be found
at this location.
=> Syslinux MBR (4.04 and higher) is installed in the MBR of /dev/sdb.

Complete log at http://paste.ubuntu.com/15455320/

Thanks in advance for your help.