This error can be caused when the VID and PID listed in the INF file does not match the VID and PID combination programmed into the device. It can also be caused if the INF file has not been copied to the \\Windows directory.
One way to check this is to use the Registry editor that comes with Embedded Visual C++ (or a suitable registry editor on the Windows CE device itself) to check for the registry settings (Tools > Remote Registry Editor). With ActiveSync running, connect to your device then look at the registry setting HKEY_LOCAL_MACHINE\Drivers\USB\LoadClients\
In this case, the entry is 1027_24592, which corresponds to a VID of 0x0403 (1027) and a PID of 0x6010 (24592) device. If this is not the device to be installed, the message will recur.
To solve the problem, the INF files must be edited to accommodate the required VID and PID. For the D2XX drivers, edit the bold red entries in the following line in the ftd2xx.inf file:
"FTDI Dual device"=FTDI,USB\&VID_0403&PID_6010
For the VCP drivers, edit the bold red entries in the following line in the FTDIPORT.inf: