This just happened to me on Xubuntu 15.10 when 4.2.0-11-generic was installed. It wanted to leave me with one kernel. You can refer to these two posts for the detail:
http://ubuntuforums.org/showthread.php?t=2251168&page=4&p=13361806#post13361806
http://ubuntuforums.org/showthread.php?t=2251168&page=4&p=13361833#post13361833
This just happened to me on Xubuntu 15.10 when 4.2.0-11-generic was installed. It wanted to leave me with one kernel.
You can refer to these two posts for the detail:
http:// ubuntuforums. org/showthread. php?t=2251168& page=4& p=13361806# post13361806
http:// ubuntuforums. org/showthread. php?t=2251168& page=4& p=13361833# post13361833