An AJAX HTTP error ocurred. HTTP Result Code: 500 (while trying to rebuild content access perms) I have installed a module that ask me everytime to rebuild content Access Permissions, but every time I try to do it, it shows me an error I do not have idea why is it happening. Please help

An AJAX HTTP error ocurred. HTTP Result Code:  500 Debugging information follows: Path: /batch?id=172&amp;op=do Status Text: Service unavailable (with message)
Response Text:


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The problem with this was the server, the server was refusing the ajax request, maybe a php memory problem I have migrated my drupal website to a VPW