Problem after clearing the cache and installing the payment module.
I installed the module and cleared the caches.I got this error when trying to log in a client.Fatal error: Uncaught Error: Undefined class constant HASH_VERSION_MD5 /app/code/core/Mage/Customer/Model/Observer.php
Re: Problem after clearing the cache and installing the payment module.
This problem comes from the Mage module. You should disable this module from your project php bin/magento module:disable Mage_Customer Or alternatively, you can put debug in the file /app/code/core/Mage/Customer/Model/Observer.php so you can find out the reason for the error in this file
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