Class 'Xibo\Controller\Base' not found

Getting this after running Maintenance from web browser.

Fatal error: Class ‘Xibo\Controller\Base’ not found in C:\Xampp\htdocs\xibo-cms-1.8.13\lib\Controller\Maintenance.php on line 35

Xampp Apache install on Windows 10. Upgraded from 1.7.6 where Maintenance was working from the browser. Found a thread here, but the suggestions did not work. Running from a command prompt results in no data or error returned. PHP is working with an email test file from same directory.

Check to see how many different PHP installs you have on the server machine. Also, check to see if PHP was upgraded in a recent automatic package upgrade run.

Using Xamp 5.6.40. The condition exists even when a clean install of Xampp 5.6.40 and 1.8.13 is used on a new VM.