I just did a clean install of Lubuntu 14.04 on an old Acer Travelmate 2410 laptop to replace Windows XP. Everything is fine except that it won't shut down, it just hangs on the shutdown screen. Only a hard shutdown will actually shut the machine down. Specs are Intel Celeron 1.60Ghz, 1.5Gb of RAM and a 100Gb hard drive. Please can somebody point me in the right direction?