GitHub announced that it would remove RC4 support from its SSL configuration on both the website and API starting January 5th, 2015, due to several cryptographic vulnerabilities associated with RC4 that could compromise data security. This change means that users accessing GitHub via Internet Explorer on Windows XP will lose access because Windows XP supports only outdated SSL ciphers and is no longer supported by Microsoft, possessing a critical security flaw in its SSL implementation. Users are advised to upgrade to a newer version of Windows or, if that is not feasible, switch to using Chrome or Firefox for accessing GitHub on Windows XP. Despite these changes, the git client from git-scm.com remains functional on Windows XP.