What are the common pitfalls to avoid when upgrading PHP on a Windows server?

When upgrading PHP on a Windows server, common pitfalls to avoid include not backing up your existing PHP configuration files, not checking for compatibility with your web applications, and not updating any necessary extensions or dependencies. It's important to thoroughly test the upgraded PHP version before deploying it to a production environment.

// Example PHP code snippet to backup existing PHP configuration files
$sourceDir = 'C:/path/to/php';
$backupDir = 'C:/path/to/backup';
$files = glob($sourceDir . '/*.ini');

foreach ($files as $file) {
    $fileName = basename($file);
    copy($file, $backupDir . '/' . $fileName);
}