I get this message when I try to upgrade my Magento 2.0.2
Sorry, we can't take that action right now.
- Cronjobs works, no migration tool
- Repositories already in composer.json file and no data migration tool
- Logged in and key saved
As soon as you used composer without the web wizard once to install Magento or extensions, the web wizard does not work anymore.
Solution: Switch to the command line and update using composer. To see how that works, read How to update Magento2 using composer
Are you upgrading from the admin?
Have you added your public & private key from your Magento Connect acc?