Starting in September 2014, major browsers will be disabling 1024-bit roots within their trusted roots stores. Any SSL certificates chained to a 1024-bit root will no longer work on any browsers that takes this action or one that relies on another’s root store.
Customers with certificates chained to a 1024-bit root need to replace and upgrade all affected certificates to SSL certificates chained to a 2048-bit RSA or ECC root by August 31, 2014.
To make this transition as easy as possible below are a few helpful resources:
Tools for generating a new CSR for a compliant certificate.
Easily determine the key-length of your certificates.
Learn how to install a certificate on a variety of servers.
Track and manage all SSL/TLS certificates in your ecosystem.