If you encounter the "Failed to start session" error when attempting to log into the graphical interface of CentOS 7, it could be due to several different factors. This article will provide a detailed guide on how to identify and resolve this issue.

Causes of the Problem

The "Failed to start session" error can be caused by a damaged or incomplete graphical environment, missing or corrupted configuration files, application dependency issues, or inconsistencies caused by system updates.

Diagnosing the Problem

Before proceeding with any fixes, it's important to diagnose the problem correctly.

1. Access the Terminal: If you can't log in graphically, try opening a terminal using the Ctrl+Alt+F2 key combination.

2. Check System Logs: Review system logs using the journalctl -xe command or less /var/log/Xorg.0.log to find specific errors related to the graphical interface.

Resolving the Issue

Here are some steps to fix the problem:

1. Reinstalling the Graphical Environment

If the problem is related to damage to the graphical environment, reinstalling it may help.

• Uninstall the Current Graphical Environment: sudo yum groupremove "GNOME Desktop"

• Reinstall the Graphical Environment: sudo yum groupinstall "GNOME Desktop"

2. Repair Configuration Files

If the problem is caused by damaged or missing configuration files, restoring or repairing them may help.

• Restore Default GNOME Settings: You can try resetting the default GNOME settings using dconf reset -f /org/gnome/.

3. Check Dependencies

Sometimes the problem may be caused by missing dependencies.

• Install Missing Dependencies: Try identifying and installing any missing dependencies using sudo yum install -f.

4. Update the System

Updating the system might resolve the problem by fixing inconsistencies caused by previous updates.

• Update the System: Perform a system update using sudo yum update.

5. Create a New User Account

If the problem persists, it might be specific to a particular user account.

• Create a New Account: sudo adduser newuser and sudo passwd newuser to set a password.

 

The "Failed to start session" error when logging into the graphical interface on CentOS 7 can be frustrating, but in most cases, it can be resolved using one of the methods mentioned above. It's important to conduct careful diagnosis and proceed methodically through the troubleshooting steps. If the problem persists, seeking further assistance on CentOS forums or contacting support may be helpful.