What OS does your computer have? Go to the Epson support site and download the software for your OS: http://tech.epson.com.au/downloads/category.asp?sCategory=Multi_Functional&id=StylusTX100&EmailAdd=&CanEmail=&SelOS=Y&MetricIDReturned=4036965&sCategory1=Multi_Functional
and use the drop down menu to choose your OS. (With Windows 7, I know that the drivers are included in the OS so you can skip this step.)
For best results use a direct connection, with a USB cable that is 6' long or shorter.
Install the full software if it is available for your OS. Then when prompted to do so, make sure the printer is on and connect the USB cable between the printer and the computer. If needed, restart the computer.
In the case of Win7 or any other OS with these drivers included, just set up the printer and plug in the data cable. However, if the drivers are not included in the OS, then the printer may work after plugging in the data cable but the scanner probably won't. In that case, uninstall the generic driver, unplug the data cable. Then reboot the computer and install the one from the Epson site.
See the Epson support site for using the printer's software package. Please note that the buttons on the front of the unit will not work for initiating actions on the computer unless the full software is installed. Thus for Windows 7, you will need to launch your scans from the computer. Paint, Windows Fax and Scan and Photo Gallery (in Live Essentials) all can acquire scans. Some of these programs are also available for and will acquire scans in XP and Vista. (Paint is in XP, Vista and Win7; Photo Gallery comes with Vista and is available for XP and Win7; Fax and Scan is in some versions of Vista.)
I hope this helps.