In very rare cases it’s possible that due to a plugin conflict on the staging or live site you get a blank page after running the pushing process or updating plugins or themes on one of your sites.
In that case, one of the plugins on the live site is causing a fatal error. You can fix that quickly by following the steps below:
Step 1 – Find the trouble maker
You can find out what plugin is causing the error by enabling the wordpress debug.log. After enabling the WordPress debug log reload the website and open the debug.log to check the recent errors in it.
Look for any recent line that mentions
PHP Fatal Error
A complete error line could be looking like that
[13-Jun-2018 11:14:46 UTC] PHP Fatal error: Class 'ComposerAutoloaderInite9c6e5ee7d69a67b5104383b338dc6e0' not found in /home/content/a2pewpnas01_data02/63/4088363/html/wp-content/plugins/wordpress-seo/vendor/autoload_52.php on line 7
You can see here that the plugin wordpress-seo (Yoast) is throwing a fatal error.
Step 2 – Disable the trouble maker
When you’ve found out what plugin is causing the error on your website use an FTP program and delete the corresponding plugin folder or disable it by just renaming the plugin folder. Both actions have the same effect and will deactivate the plugin on your website.
You find all WordPress plugins in the folder wp-content/plugins.
Your website is reachable again. Now you can move on and either push the plugin again from the staging site with WP Staging Pro or install it again from its original source like the WordPress plugin repository by installing it from WordPress > wp-admin > plugins.
If the plugin throws that error again you can open a support ticket and we help you to resolve it. It also may be helpful if you let the developer of the plugin know about that error so that he is able to fix the error.