The process of updating or upgrading plugins, themes and WordPress itself will usually turn on maintenance mode. And it all runs automatically without needing to do anything. Usually WordPress will display the message “Briefly unavailable for scheduled maintenance. Check back in a minute. “During maintenance mode is active for the update process.
What if you are having problems in the process? Among the update process is canceled and returned to normal, or even stuck in maintenance mode and make the pages of your website can not be accessed by visitors. Well … how do I fix this?
Actually easy anyway to restore the look of your WordPress blog to the original, which you definitely need access to the installation directory on your hosting. This can be through the File Manager in cPanel or using FTP account.
If this is shared hosting then the public_html or www folder will be named .maintenance file, delete it. Then your site will be opened normally back. If the means had failed to fix the problem persists or it may be due to a conflict plugin or theme, just delete it manually and will use the WordPress default theme manually.