Check the Windows Device Manager in Control Panel. If it is listing an unknown device when Esplora is plugged in, click Update Driver. Point it at your Arduino IDE 1.05 install directory which should have the Esplora driver.
If the lights are still blinking on the board, it sounds like more of a driver issue.
If you have access to a different computer, you could try to talk to the Esplora via the 1.05 IDE on that to ensure it is not a board issue.