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I'm new to Magento and installed today the SUPEE7405 patch without SSH.
Now I have a blank admin page and cant get it back running. I cleared var/session and var/cache. I checked the includes/config.php that the compiler is disabled. I activated the error message and received

Fatal error: Class 'Mage_Core_Helper_UnserializeArray' not found in app/Mage.php on line 547

Has anybody got a idea to solve the problem.

marked as duplicate by Marius Jan 21 '16 at 11:55

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  • 1
    Which version of Magento are you running ? Is the following file present on your system app/code/core/Mage/Core/Helper/UnserializeArray.php ? – Raphael at Digital Pianism Jan 21 '16 at 9:23
  • I'm using Version 1.9.2.1. No, no UnserializeArray.php in the folder – DBR Jan 25 '16 at 9:07
  • 1
    The app/code/core/Mage/Core/Helper/UnserializeArray.php was only introduced in Magento 1.9.2.2 it sounds to me like you downloaded the patch for version 1.9.2.2 and not for version 1.9.2.1. You should download this patch: magentary.com/wph/contentary/uploads/SUPEE-7405-1.9.2.1.zip – Raphael at Digital Pianism Jan 25 '16 at 9:16
  • Thanks for the hint. I just checked the zip I downloaded before. Zip File is named 7405-1.9.2.1 and the files seem to be equal to the zip in youre recommended link. I downloaded the Supee 6788 and found the UnserializeArrey.php. It seems the Admin before did not update as he supposed to. I'm not shure if I can just push the 6788 over now. – DBR Jan 25 '16 at 9:28
  • 1
    Applying 6788 fixed it for me. – sho Mar 16 '16 at 22:34

You have here a list of known bugs after patching Magento : https://magento.stackexchange.com/a/98236/33619
Some people are trying to fix them

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