PayPal recently sent out an email regarding "upgrading the certificate for www.paypal.com to SHA-256". In this email they "advise that you consult with your individuals responsible for your PayPal integration. They will be able to identify what, if any, changes are needed."
This change requires no change to be made to the MemberMouse plugin.
However, there is a chance that it may be incompatible with some server environments and could potentially prevent your MemberMouse install from receiving and/or processing IPNs correctly. While we expect that most hosting environments will be unaffected, to ensure that you are prepared and to prevent any possible disruption in service, we recommend that our customers using PayPal reach out to their hosting providers to ensure that their hosting environments are SHA-256 compliant.
Hosting providers can be referred to PayPal?s microsite created for this issue for more information: https://www.paypal-knowledge.com/infocenter/index?page=content&id=FAQ1766&expand=true&locale=en_US
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