Take the 2-minute tour ×  I'm developing an USB driver for an
embedded device, which appears to Windows as a CDC (virtual COM)
device. I'm using Free Serial Port Monitor and Realterm to
interact with the device.  Whenever I reset the device the COM
port effectively disappears from the system, even though it may
be "open" by these utilities. When the device is restarted the
COM port re-appears in Device Manager, as expected. However,
neither Free Serial Port Monitor or Realterm can find it. My
suspicion is that the port is somehow locked.  I need a tool for
observing any locks on COM ports and a way of unlocking the
port, short of rebooting the computer, which I've been doing
(very time consuming). Does such a utility exist?  share|improve
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accepted  Disabling the device in Device Manager, and then re-
enabling it, freed the device for use.  share|improve this
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