I had the same problem and found out another driver was opening the port on boot up. To find out which program it is go to : Start | Run | and then type "msconfig" (without the quotes), select the Startup Tab and uncheck everything except:
"ScanRegistry", "TaskMonitor", "SystemTray", & "LoadPowerProfile". Click OK to accept the changes, and reboot the computer. If this allows you to log on, go back to the System Configuration Utility, and try rechecking the boxes unchecked previously, one or a few at a time until you find the culprit.
Good Luck,
Happy Thanksgiving to everyone in the group!
Jay Merritt

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