The pop up windows are something I am not aware of. If you could screen shot them next time I would take a look. There are a couple of things to conisder when you see the default page, but not the openstack login.

If the devstack script has not finished running, or has errors,  the apache package is installed and the daemon is running, but the OpenStack backend and memcached may not yet be up and running. Until horizon is up the default page would be seen. Revisit the ./stack.sh output in the log file and see if there are errors having to do with horizon or keystone that would prevent the service from fully coming up. 

After reboot devstack is not running. This was a more recent change to the devstack code. After a reboot you would need to run stack.sh again in order to start the necessary services. The good news is the packages and code is already in place so it will quickly check that things are were they need to be and start the services.

If there are no issues with the ./stack.sh and it is not after a reboot then please go to /var/log and look for recent keystone or horizon errors. From that output we can investigate the issue further. 

Thank you. 

I am getting a Keystone error during ./stack.sh. See my earlier comment above.

Please use the "Start over" button and run through the labs a second time. An update  will soon be been pushed to the lab content. The fix is to call a previous version of DevStack instead of the bleeding edge version. 

git clone https://git.openstack.org/openstack-dev/devstack -b stable/liberty

DevStack changes all the time. OpenStack also changes a lot. The ongoing change can mean working with the product is less stable than a single-vedor, propriatary, unchanging tool. By using the -b option a previous, more stable branch can be used. While this is more stable it may not have the newest and most interesting featurs of OpenStack. 

Thank you for leaving a post about the issue