ReadyNAS 102

I guess maybe you are using the web interface instead of browsing to the share in File explorer (assuming windows)? If so try chrome browser. If not I don't know, I have a RN104 and was able to copy a single folder with over 30G of files no problem at all last night. You say 1 file, have you tried moving something large like a multi GB ISO? If it copies, does it go quickly and smoothly? if not maybe something basic like a bad network cable? PS you are not trying to copy 30GB over WiFI are you? if you are try a cable , see if that helps. many wifi setups are not good enough to move that much data without problems, but are good enough for smaller transfers.