How can PHP users troubleshoot errors related to file existence and directory paths during file operations?

When troubleshooting errors related to file existence and directory paths during file operations in PHP, users can use functions like `file_exists()` to check if a file exists, `is_dir()` to check if a directory exists, and `realpath()` to get the absolute path of a file or directory. Additionally, users can use relative or absolute paths when specifying file or directory locations to ensure the correct path is being accessed.

$file_path = 'path/to/file.txt';

if (file_exists($file_path)) {
    echo "File exists!";
} else {
    echo "File does not exist.";
}