I recently installed ubuntu for dual boot with windows and I wanted to upgrade to ubuntu 11.04. I launched the update manager application and clicked on the upgrade button at the top of the window and it started fetching files, bla bla bla... It unexpectedly stopped/stacked at the third stage. i.e Getting new packages while fetching file 1309 of 1309 and then on a second trial it goes on fetching until file 1360 of 1362 and failed. May be in the future it will try to fetch file 1000000 of 1000001 and then stop and then I can never have ubuntu 11.04 ever. Can anyone come up with a wise but uncomplicated solution for this problem. Thanks in advance.