更新管理器无法计算升级
最近，在运行更新管理器时，以及检查包信息之后。 显示此消息。
Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade. Please report this bug against the 'update-manager' package and include the following error message:'E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.' 下载更新，看看会发生什么。 sudo apt-get upgrade