Epson recently released a printer driver for the TM-U220 that is compatible with Windows7 64 bit. DO NOT PLUG THE PRINTER INTO THE COMPUTER UNTIL AFTER THE DRIVER IS INSTALLED. Here is a link to download the driver.
1. Once the driver has finished downloading to your computer double click on APD_453.exe

2. If asked Do You Want To Allow This Program To Make Changes To This Computer select Yes

3. When the InstallShield Wizard window comes up select Next

4. Next Accept the license agreement and click Next

5. Next select the Minimum type of install and select Next

6. In the Printer Configuration window select ADD

7. In the Add Printer window use the drop down next to Select Driver and find the Epson TM-U220 Receipt and in the drop down menu next to Port Type select Create a USB Port and select Next

8. You will now see the EPSON TM-U220 Receipt in the Printer Configuration window. Select Next

9. Click Next through the Start Coping Files window

10. When the installation is complete select Finish

11. Now plug the printer into the computer and make sure the printer is turned on

12. Next, go to Start and then Devices and Printers and you should see your Epson TM-U220 installed

13. Right click on the printer and go to Printer Properties

14. Select Print Test Page to ensure the printer is working.

15. If you were successful in printing a test page the close all of the printing windows and open the Point of Sale. If the Point of Sale was open, close it and reopen the Point of Sale.

16. In the Point of Sale select Setup>POS Setup>Print Options and under Receipt Printer select the Epson TM-U220 and for Receipt Font select Font A11