I logged into the WordPress Admin panel for this site the other day and noticed the site had four plugins requiring an update. So off to the Updates page I went, where I selected all plugins affected and pressed the Update button.
Sadly, this didn’t run as smoothly as normal.
Instead, mid-process the frame was replaced with a Site in Maintenance Mode message screen, which of course if you tried any other page of the site, both normal and administrative panel, remained there.
Basically one of the plugins had failed during the update process, thus leaving the site stuck in Maintenance mode and most likely inoperable thanks to the broken plugin.
First things first, I fired up my FTP client and browsed to the home directory for this site where I spotted a .maintenance file – which I promptly deleted.
With the maintenance mode now ‘disabled’, I refreshed a page and noted the error message displayed pointed to the JetPack plugin update as having failed – of course I was lucky here, sometimes it is impossible to know which plugin update failed, which makes the next step slightly harder.
Because I knew that the JetPack plugin was the culprit, I headed off to wordpress.org to download a fresh copy of the plugin, which I then unzipped and installed via FTP to the wp-contents/plugins folder, overwriting the contents of the existing jetpack folder. (If you don’t know what plugin crashed, you’ll have to do this process for all the plugins you were updating.)
The FTP upload complete, I refreshed the page and was relieved to see my site back in all of its former glory.