FTP Connection gets dropped

Hello! I have a Dell T7500 Running Windows 7 Professional. This computer is connected via FTP to a CNC machine control. The machine control is 'drip fed' programs via this FTP connection because the files are too large to put completely into the controls memory. With XP this was setup and working fine. I set the timeout to the equivalent of approximately 15 days... or (1,315,000 seconds)...