Os Solution products have fixed an issue in the Paypal payment gateway in five of their extensions and made new releases to fix it:-
1. Events Booking version 2.14.2 https://www.joomdonation.com/forum/events-booking-general-discussion/57320-events-booking-version-2-14-2-released.html
2. Membership Pro version 2.8.3 https://www.joomdonation.com/forum/membership-pro/57321-membership-pro-version-2-8-3-released.html
3. Eshop version 2.5.4 https://www.joomdonation.com/forum/released-versions/57293-eshop-2-5-4-was-released-at-21-march-2017.html#96127
4. OS Services Booking 2.5.3 https://www.joomdonation.com/forum/os-services-booking/57336-version-2-5-3-paypal-security-announcement.html
5. Joom Donation version 4.6 https://www.joomdonation.com/forum/joom-donation/57334-version-4-6-paypal-security-announcement.html
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