Drivers for this Belkin F5U409 USB to Serial Adapter are quite old. This device uses a MCT board, use the additional drivers link below for the latest MCT drivers.
Belkin F5U409 Driver
File: F5U409 _winxp_v2.exe
4c1af201964c160799551ea9a44bc70dd65b94ee4b0bd460085a81ed4ac4057f
Belkin F5U409 Driver
File: F5U409 _winxp_v2.exe
2285ed3328da2ab0aba25bcd6b129f301b20597d730715d15c13b7aa62959f25
Belkin F5U409 Driver
File: F5U409 _win98_me_v2.exe
7bf292daa167189432a0ff6232f0b65fc06b613527c96bd1179cf832909a3f06
Belkin F5U409 Driver
File: F5U409_mac_v2.sit
e8178836a5ea43f6068746548eca48113fb14793a22902c8e99b528789ee015e