Windows 9x and Windows NT4 driver for IS560RK (ISA) modem with Rockwell chipset. After unzipping file to a temp folder, be sure to READ the README files for instructions. This file is a 2 part set which contains firmware upgrade and driver. Just be sure to read the instructions before using and make sure it applies to your current modem revision.
Note: Mecer is only ONE vendor for this chipset... it could be for numerous other brands including Actiontec.