TLS requirement for repo.magento.com
The Magento software and component repository,
repo.magento.com, recently started requiring Transport Layer Security (TLS) 1.1 or later.
The PCI Security Standards Council} removed SSL/TLS 1.0 as an example of strong cryptography from the PCI Data Security Standard (PCI DSS) version 3.1, stating that it can no longer be used as a security control after June 30, 2016.
For details, see Date Change for Migrating from SSL and Early TLS.
If you have an earlier version of TLS, you’ll see the errors discussed in this section.
Downloading a Magento metapackage
The following error displays if you attempt to run
composer create-project to get a Magento metapackage:
[Composer\Downloader\TransportException] The "https://repo.magento.com/packages.json" file could not be downloaded: Failed to enable crypto failed to open stream: operation failed
Using the Web Setup Wizard
Actions like saving your authentication credentials or synchronizing with Magento Marketplace fail with the following error: