Das steht im mod_warning_adim_2016-12-06.log
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: 1146 - Table 'XXX_XXXXXX.paypal_config' doesn't exist<br/><br/>SELECT config_value
FROM paypal_config
WHERE config_key = 'PAYPAL_LOG_LEVEL' in File: /var/www/virtual/bombahunter.com/htdocs/inc/db_functions_mysqli.inc.php on Line: 161
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: Backtrace #0 - /var/www/virtual/bombahunter.com/htdocs/includes/external/paypal/classes/PayPalCommon.php called at Line 112
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: Backtrace #1 - /var/www/virtual/bombahunter.com/htdocs/includes/external/paypal/classes/PayPalPayment.php called at Line 71
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: Backtrace #2 - /var/www/virtual/bombahunter.com/htdocs/includes/modules/payment/paypalcart.php called at Line 28
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: Backtrace #3 - /var/www/virtual/bombahunter.com/htdocs/admin/modules.php called at Line 263
[06-12-2016 10:01:19] E_USER_WARNING : LoggingManager: Backtrace #4 - /var/www/virtual/bombahunter.com/htdocs/admin/modules.php called at Line 321
Die Tabelle paypal_config wurde bei der Installation nicht angelegt.
Entweder das Modul nochmal deinstallieren und neu installieren, oder die Tabelle per Hand ins SQL schreiben.
Bei mir waren es die Berechtigungen, die die Anlage von Tabellen verhindert haben. Das bedeutet, der SQL-Benutzer (mein Shop) hatte zwar alle Berechtigungen, in den Tabellen zu schreiben, durfte aber keine Tabellen selbst anlegen und verändern. Vielleicht liegt Dein Problem auch da, wenn eine Neuinstallation nichts bringt.
Aber bei mir läuft Paypal auf einmal auch nicht mehr.
[06-12-2016 11:32:42] PayPal\Core\PayPalHttpConnection : INFO: GET https://api.paypal.com/v1/payment-experience/web-profiles/XP-LG4B-8ZGD-LQB4-RZVH
[06-12-2016 11:32:43] PayPal\Core\PayPalHttpConnection : INFO: Response Status : 404
[06-12-2016 11:32:43] PayPal\Core\PayPalHttpConnection : ERROR: Got Http response code 404 when accessing https://api.paypal.com/v1/payment-experience/web-profiles/XP-LG4B-8ZGD-LQB4-RZVH. {"name":"INVALID_RESOURCE_ID","debug_id":"989b657c883c5","message":"The requested resource ID was not found","information_link":"https://developer.paypal.com/webapps/developer/docs/api/","details":[]}
[06-12-2016 11:32:43] PayPal\Core\PayPalHttpConnection : INFO: POST https://api.paypal.com/v1/payments/payment
[06-12-2016 11:32:44] PayPal\Core\PayPalHttpConnection : INFO: Response Status : 400
[06-12-2016 11:32:44] PayPal\Core\PayPalHttpConnection : ERROR: Got Http response code 400 when accessing https://api.paypal.com/v1/payments/payment. {"name":"INVALID_EXPERIENCE_PROFILE_ID","message":"The requested experience profile ID was not found","information_link":"https://developer.paypal.com/docs/api/#INVALID_EXPERIENCE_PROFILE_ID","debug_id":"8e7a0b7348e69"}
[06-12-2016 11:32:45] PayPal\Core\PayPalHttpConnection : INFO: POST https://api.paypal.com/v1/payments/payment
Ein Klick auf den Button im Warenkorb führt zu einer leeren Seite.
.. /shopping_cart.php?action=paypal_cart_checkout