As you update/add/remove associated pieces of software on a SharePoint server you might run into this error.
It is common for update/add/remove to modify registry settings. Unfortunately, some of these registry settings might be critical to SharePoint. In this case this made SharePoint result in ‘trial period for this product has expired’ error. Oddly, you could open the http://<SITE>/_layout/settings.aspx page, but no other pages.
I ran the following command and rebooted the server:
psconfig.exe -cmd secureresources
This made the needed changes to the system registry keys for SharePoint.