In keeping with industry standards set by the Certification Authority/Browser (CA/ B ) Forum, PayPal will discontinue supporting 1024-bit key length certificates and will migrate to 2048-bit certificates before the end of 2013.
We have completed the installation of 2048-bit certificates for all API endpoints in our PayPal Sandbox and Payflow Pilot environments, and we will be doing the same for our production environments starting on August 5, 2013. A complete upgrade schedule is available here.
We strongly encourage merchants to thoroughly test any existing integration(s) in the PayPal Sandbox and/or Payflow Pilot environments to ensure this migration will not cause any unforeseen issues.
Please have the team or person responsible for your integration refer to the following:
If you need to import the new PayPal Sandbox and/or Payflow Pilot server certificates to your application or system truststore, you can download production and Sandbox certificates from https://ppmts.custhelp.com/app/answers/detail/a_id/952.
If you don't typically import the server certificates to your truststore, you can proceed with testing with no other action required.
If you have any questions, please contact PayPal Merchant Technical Services by filing a ticket; refer to PP-LIVE-3503. You may also visit our Live Site Status blog.