lib/Dropbox/RootCertificates.php
static function useExternalPaths()
    {
        if (!self::$useExternalFile and self::$paths !== null) {
            throw new \Exception("You called \"useExternalFile\" too late.  The SDK already used the root ".
                                 "certificate file (probably to make an API call).");
        }

        self::$useExternalFile = true;
    }
static function useExternalPaths()
    {
        if (!self::$useExternalFile and self::$paths !== null) {
            throw new \Exception("You called \"useExternalFile\" too late.  The SDK already used the root ".
                                 "certificate file (probably to make an API call).");
        }

        self::$useExternalFile = true;
    }
If you're running within a PHAR, call this method before you use the SDK
to make any network requests.

Normally, the SDK tells cURL to look in the "certs" folder for root certificate
information.  But this won't work if this SDK is running from within a PHAR because
cURL won't read files that are packaged in a PHAR.