I had the same issue. It was clean installation as replacement of windows 7 on Lenovo T440s. First instalation cycle was ok but there was something bad with parttiions, I thought it was because I wanted to keep untouched partition for Intel Rapid Start Technology and recreated only some partitions but it was https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1387654 Next two installation cycles was frozen on partition creation (I completely removed and recreated partitions). Third cycle was ok.
I had the same issue. It was clean installation as replacement of windows 7 on Lenovo T440s. First instalation cycle was ok but there was something bad with parttiions, I thought it was because I wanted to keep untouched partition for Intel Rapid Start Technology and recreated only some partitions but it was https:/ /bugs.launchpad .net/ubuntu/ +source/ ubuntu- release- upgrader/ +bug/1387654 Next two installation cycles was frozen on partition creation (I completely removed and recreated partitions). Third cycle was ok.