The MC990D offers quand-band GPRS/EDGE service (850/900/1800/1900MHz) as well as UMTS 3G service (2100MHz) and can be installed on Mac OS X 10.4 or later.
Insert the MC990D into an available USB port on the Mac. The device will be detected automatically and will be mounted as a storage drive:

Double click the icon for the "installer.pkg", the installation wizard will start automatically:
To install the MC950D on your PC, simply insert the device into an available USB port on the PC. Windows will detect new hardware automatically and install the necessary drivers and software. Once installed, the software will be displayed automatically:

Before you can connect to the Internet, you must first create a connection profile. To do this, right click on the icon in the system tray and select Settings → Profile Manager: