What common issue can arise when using the simplexml_load_file function in PHP?

When using the simplexml_load_file function in PHP, a common issue that can arise is that the function may not be able to load the XML file due to various reasons such as incorrect file path, invalid XML format, or insufficient permissions. To solve this issue, you can check if the file exists before attempting to load it and handle any potential errors that may occur during the loading process.

$file = 'example.xml';

if (file_exists($file)) {
    $xml = simplexml_load_file($file);
    if ($xml === false) {
        echo "Failed to load XML file.";
    } else {
        // Process the XML data
    }
} else {
    echo "XML file does not exist.";
}