Installing Magento 2 Installation Problem in Magento_ConfigurableSampleData @ %67

[Fadynagy]

This is the same my problem .. Did you have the solve ??

[StruggleSnuggl3]

If you are running litespeed then you might have to add to your .htaccess since LiteSpeed follows the strict process running to reduce cpu/memory consumption.

https://www.litespeedtech.com/support/wiki/doku.php/litespeed_wikihp:run-without-timeouts#through_th...

[ardhra_kkalesh]

I am facing the same issue in Magento 2. 
I just solved the issue by removing the 'maintenance.flag' file from the root directory.
sudo rm /opt/lampp/htdocs/your_foldername/var/.maintenance.flag
Pls remember one thing it may take some time for the installation process