Most likely you have blocked port 80. Also rather than using the control panel to start Apache, you may want to go to XAMPP's root directory and call Apache-start.
It looks like either the mentioned file is missing or there might be some other server error. The best solution is, to take a backup of two directories “htdocs” and “mysql" by copying these to some other location.
Then reinstall the xampp. And restore these two folders by copying them back. You can also take backup of any other setting or configuration that you have done.
Hope this resolves your Query !!
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