To make sure I understood you correctly: you have a desktop computer at home and a portable computer you take with you. When being someplace outside your home you want to establish a connection from your portable to your desktop computer to up- or download files. Is that correct?
Is your desktop computer directly connected to the Internet, or is it behind a router? What operating system is running on it? Would using SSH be an option for file access? There are very nice GUI-SSH-clients for Windows.
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