how to delete USB COM port assignments

E

edd

After installing a USB to Serial adaptor I've found that often when the
adaptor is removed and reinserted the old COM port is not necessarily
used. So, several COM ports are assigned to the device and when I need
to get at COM1 and COM9 to install a new device they are in use.
Even un-installing the USB-serial adaptor does not free up the
ports. What are the registry hacks that would allow these ports to be
reused or shown to be free? Or is there some system mod software that
would do it?

I did find some registry entries but when I tried to delete the
entries, Delete was not allowed.
 
Y

Yves Leclerc

You can not! Only the newest one "seems" to appear. How can you remove to
"older" ones if they do not get listed?
 
B

Bob I

Show Hidden enabled? Or View, Show Hidden.

Yves said:
You can not! Only the newest one "seems" to appear. How can you remove to
"older" ones if they do not get listed?
Click to expand...
 
S

Si Ballenger

After installing a USB to Serial adaptor I've found that often when the
adaptor is removed and reinserted the old COM port is not necessarily
used. So, several COM ports are assigned to the device and when I need
to get at COM1 and COM9 to install a new device they are in use.
Even un-installing the USB-serial adaptor does not free up the
ports. What are the registry hacks that would allow these ports to be
reused or shown to be free? Or is there some system mod software that
would do it?

I did find some registry entries but when I tried to delete the
entries, Delete was not allowed.
Click to expand...

XP has a bug associated with assigning com port addresses to USB
devices. Every time the device is connected, it is assigned a
higher com port number. In the advanced section of the com port
setup in device manager when the device is connected, you can
just reassign the port number for the device to a lower port
number that you know is not in use, and ignore the windows
warning. I've done this with my USB/serial port adapter and XP
seems to remember the assigned com port after that. Check the
link below for some info.

http://www.modemsite.com/56k/xptip.asp
 

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