Unable to log on to Ubuntu, GNOME power management configuration problems

Ubuntu cannot be logged on. The environment variable settings of Ubuntu were modified two days before the GNOME power management configuration problem. The/etc/profile file and/etc/bash were modified. bashrc files. You cannot log on after restarting. I thought it was an environment variable problem. Ctrl + Alt + f2 entered the command line mode and deleted the modified configuration. I thought it was normal, I did not expect the "GNOME power management configuration error" prompt message to be displayed during login. After a variety of explorations and attempts, I finally found that this problem was not caused by my configuration modifications, but because the system disk space was insufficient. Run the df-h command to check the usage of the system disk. If you encounter this problem and your disk space is insufficient, try to delete some items and free up some space, restart again. If the problem persists, try another method.