Apache Web Server Stops Running on My Mac

[wcamp]

Hi:

For no apparent reason, the Apache Web Server stops running after I activate the Start All button on XAMPP v. 7.4.18-0. XAMPP has been reliable for me for more than four years. Might this problem be caused by my upgrading to Mac OS 11.3 (Big Sur)?

When I attempt to open a web page file (by right-clicking the selected file in Dreamweaver's list of files), I get the following error message on Safari and Chrome: "Cannot connect to the server 'localhost.'"

I've Google-searched "apache web server stops in XAMPP on Mac" but found nothing helpful. A number of search results highlight using the XAMPP Control Panel to change port configurations but, alas, XAMPP doesn't appear to have a Control Panel for Macs.

What's needed to get XAMPP for Mac to be reliably functional again? Thank you.