Which of the following is NOT typically a factor when transferring files?

The factor that is NOT typically considered when transferring files is the storage size of the recipient device. When files are transferred, the primary concerns usually involve how the data will be transmitted, such as the transmission mode, which dictates the format and method of data transfer (e.g., packet-switching versus circuit-switching).

Additionally, the file structure is pertinent because it relates to how the data is organized within the file, affecting compatibility and how the receiving system will interpret the file correctly. The data type is also a crucial consideration, as it informs the receiving system about how to process and handle the data accordingly.

While adequate storage on the recipient device is important to receive files, it is not a direct factor in the mechanics of the transfer itself. A transfer can occur regardless of whether the recipient's device has enough space; however, the successful receipt and utilization of the file afterward is contingent upon sufficient storage. Therefore, out of the given options, the storage size of the recipient device is the least related to the act of transferring the files.