To use Sharing Folders, both you and your contact must be using Windows Live Messenger 8.0 or a later version. Sharing Folders might not work if: You're logged in as a guest without privileges to send or receive files. *You or your contact have a FAT32 partition (A partition can be a section of your hard drive, or the entire drive. Partitions are usually created before the operating system is installed. For most home users, the hard drive has only one partition.) . For Sharing Folders to work, you will need to convert the system partition to NTFS (A file system that provides performance, security, reliability, and other advanced features.) . For more information, see Unable to use Sharing Folders. *Windows Live Messenger was set up by someone who doesn't have administrator privileges and can't give access to other users. *You or your contact has a Messenger add-in that interferes with Sharing Folders. *You haven't installed a security update that you need to have to share folders. *You don't have enough free hard disk space.
هذا من موقع الشركة انظر فى احد تلك الاسباب ، وربما كان من نوع التقسيم كما ذكر FAT / NTFS