The system is running in low-graphics mode

开机启动ubuntu发现报了一个错：

问题描述

解决方案

When the message that "your system is running in low-graphics mode" appears, press Ctrl + Alt + F1 , then login with your credentials. And then, run the following commands: sudo apt-get install --reinstall ubuntu-desktop. sudo reboot.之前在ubuntu上配置过一些东西，我不希望重新安装，此法不行。