I search on google but not getting any proper solution. Does anyone has any solution for this ? I am getting this error from admin panel while readiness check for upgrade magento 2.0.7 version.
The error is quite user friendly and is saying to set cron job on server. Set below to execute after every 5 minutes on server
php yourMagentoPath/bin/magento cron:run
And perform the check again.
[Cause] :- To upgrade Magento it is must to set a cron job unless you are upgrading using composer. There are many other rediness checks that will only be performed once this cron is set. Try this once and share if it worked.
Apart from this the better way to upgrade Magento is to use composer. Its easy to upgrade using this method and it take less time(Never run composer as root user). By using this method roll-back is also very easy just make sure you have backup of your database as check this issue.