I was helping a friend install ubuntu via windows installer, creating a dual boot. We used os-uninstaller to uninstall windows xp, but it did not completely delete the dual boot. When we rebooted his computer, but it displayed BOOTMGR not found. Please help asap!

He's using a Lenovo T60 with BIOS 2.0, recently running Windows XP, and Ubuntu 12.04 LTS.

Please help!