I've a 1TB HDD that I use for extra storage. Today I tried to connect it to my MBA for the first time to transfer some files. While I can copy the files from the external HDD to the MBA without issues, I am not able to transfer files from the Macbook Air to the external drive. Copy+Paste, Drag and drop nothing seems to work. It is a Seagate external hard drive if it matters. Can anybody tell me if I am doing something wrong? What do I need to do to be able to transfer files over to the external drive?