How to Disable USB Port

Step 1:  Goto run...
Step 2:  Type 'regedit' without quotes...
Step 3:  Click on HKEY_LOCAL_MACHINE...
Step 4:  Go to SYSTEM...
Step 5:  Click on CurrentControlSet...
Step 6:  Click on services...
Step 7:  Go to USBSTOR...
Step 8:  Double click on 'Start' where value is 3...
Step 9:  Now change the value data with 4...
Step10: Now press ok

Refresh your desktop your USB port is disabled, to enable the usb port replace the value 4 with 3...