Internal Server Error

I messed up my site.
I was trying to update my opencart lightning accelerator.
I uploaded the files then went in and uploaded the xml file in the extension installer. It installed successfully.
Then I went to the modification page and clicked refresh.
The site went down.
I tried to go through and delete the lightning program, just to get the site back up. It will not come back up.
Still internal server error.
I need help, losing out on sales because the site is down.
What can I do to get back up and running?

You need to at least display the error messages or get it from error log. Then copy it here.

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

You need to find your error logs. OpenCart one is in system/storage/logs. You might also find a PHP error log defined by the PHP error_log setting.

Do you not have a backup you could compare or restore from? Or maybe your host has a back?

Thank you for trying to help. I got the site back up and working. The problem was a modification folder created by the lightning program. As soon as I removed the modification folder the problem cleared up. It was not creating an error in the logs that I could find. Thank you again for trying to help.