phpThumb write test FAILED

I'm trying to deploy my PHP website in Godaddy Windows shared hosting with IIS7. My site using phpThumb library to generate thumb images.

But the thumb images are not displayed, I got:

Usage: /########/filename.jpg read Usage comments for detail

When I check phpThumb.demo.check.php, the red error occur at cache write test as below

D: / Hosting / ########### / cache / 6 / 67 / 67c / 67c4 / phpThumb_cache_########__raw67c44e91c46b79493d95da579a7fef28_par52b4fbd9e2256843fcdbe9d1f35f2875.jpeg
directory does NOT exist (before EnsureDirectoryExists())
directory does NOT exist (after EnsureDirectoryExists())
write test FAILED

The directory D: / Hosting / ########### / cache already exists and already changed as writable from godaddy file manager.

But I note both "cache directory" and "temp directory" check result is "exists/readable/writable".

Why does phpThumb give "write test FAILED" although cache directory is exists/readable/writable ? And when I check cache folder, CacheStart.txt file is created.

For Godaddy windows share hosting, I did below changes and working for me. There may be other better solution but I just try quick change to work for me.

at phpthumb.functions.php //it will fix creating sub folders in cache dir, optional without it cache will not generate

static function EnsureDirectoryExists($dirname) {
    $dirname = str_replace('/', DIRECTORY_SEPARATOR, $dirname);  //added for godaddy
    $directory_elements = explode(DIRECTORY_SEPARATOR, $dirname);
    $startoffset = 5;  //added for godaddy

    /*  comment for godaddy
    $startoffset = (!$directory_elements[0] ? 2 : 1);  // unix with leading "/" then start with 2nd element; Windows with leading "c:\" then start with 1st element
    $open_basedirs = preg_split('#[;:]#', ini_get('open_basedir'));
    foreach ($open_basedirs as $key => $open_basedir) {
        if (preg_match('#^'.preg_quote($open_basedir).'#', $dirname) && (strlen($dirname) > strlen($open_basedir))) {
            $startoffset = count(explode(DIRECTORY_SEPARATOR, $open_basedir));
            break;
        }
    }
    */
    $i = $startoffset;
    .....

at phpthumb.class.php //it is required, without it sourcefilepath got wrong

function ResolveFilenameToAbsolute($filename) {
    ....
    if ($this->iswindows) {
        //$AbsoluteFilename = preg_replace('#^'.preg_quote(realpath($this->config_document_root)).'#i', realpath($this->config_document_root), $AbsoluteFilename);
        $AbsoluteFilename = str_replace(DIRECTORY_SEPARATOR, '/', $AbsoluteFilename);
    .....