I have installed Magento 2 CE Version 2.1.0. I'm doing System Upgrade on my Linux Server
It gives below error
[UPDATE]
Instead of GUI i'm using CLI.
How to update Magento2 using composer
I'm using @Mukesh Chapagain Solution
Updating/Upgrading to Magento 2.X.X (via composer) Latest is 2.1.1
composer require magento/product-community-edition 2.X.X --no-update
composer update //If your receive out of memory error then in apache php.ini please update your memory_limit 7680000M Example
rm -rf var/di var/generation
php bin/magento cache:flush
php bin/magento setup:upgrade
php bin/magento setup:di:compile
php bin/magento indexer:reindex
After upgrade, check your Magento version with the following command:
php bin/magento --version
Worked for me :) Why it doesn't work with GUI?

appfolder has770permission – Jackson Oct 14 '16 at 03:24