Do you have the proper COM port set in the RepRap Host software?
Your port under Windows 7 is probably COM3 (although it could be something else).
Verify what the com port is and then in the RepRap Host Preferences dialog window, Globals tab, make sure that the BaudRate is correct for your firmware (by default 19200) and the Port (name) (left hand column, bottom) is correct "COM3" or whatever is correct for your system.
Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
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