Also I have had issues with a Paypal based script -called Quicksell. The IPN isn't getting through and customers aren't getting their orders.... following the documentation, I had disabled the CSRF/Anti-spam form protection (CSRFShield) but the problem was happening anyway. When I spoke to the Quicksell developer, he said a firewall could be the problem.
I'm wondering if there needs to be some security exceptions for these components, but I'm not sure how to set it up. My office has superfast internet and the latest browsers, but some customers have older browsers, different set ups...the result being that so far, I have been unable to duplicate the errors - all I can do is field the complaints and view the components' backend, seeing that orders confirmed by Paypal are not registered in Quicksell. I see security exceptions for legitimate looking username and passwords failing to login. Trying 3-4 times with the same combination like they expect to be able to login but looking at the user manager and seeing no such username recorded.
I have had both of these extensions for over a month and neither of these issues came up until the installation of Admin Tools, which makes me think it's something to do with the firewall.
Thanks for any help you can provide