I followed the upgrade instruction:
composer require magento/product-enterprise-edition 2.1.1 --no-update composer update
Then I get this error message:
Your requirements could not be resolved to an installable set of packages. Problem 1 - The requested package magento/product-enterprise-edition could not be found in any version, there may be a typo in the package name. Potential causes: - A typo in the package name - The package is not available in a stable-enough version according to your minimum-stability setting see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.
In my case git was only used to clone Magento2 repo for the installation purpose, and it was really quick and easy. However I didn't realise the issue afterwards that I'm unable to upgrade my Magento2.
I did try to setup git and I forked a copy of magento2 repo to use it as my remote origin. But because I'm very limited in git, things get worse and worse, and I messed up my whole local code base, had to restore it via a backup copy.
After all the hassle I wish I never used git for the start, is it possible to upgrade Magento without using git at all (although it was installed by git)?