If you see white empty screen trying to access your PrestaShop store, it means that there is some server error occurred.
Enabling errors display
First of all, you can enable built-in Debug Mode of PrestaShop engine, open config\defines.inc.php file and locate the following line:
replace it with
Enabling errors logging
To log the errors without displaying them, you need to open index.php file from the root of your PrestaShop installation and at the top add the following code:
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