Serial port locks when Windows boots

[jh]

Have a problem with a serial device (a scale) that, when
plugged in when booting up Windows, prevents any program
from connecting to the port once booting has completed.

Symptoms are as follows -

- scale device streams data continuously to the port (i.e.
there is no prompted input). Connection is at baud rate
9600. Scale does not make allowance for hardware flow
control.

- when the scale is connected to the PC, during booting
the mouse and keyboard devices will hang for about 10
seconds around the login screen.

- when the scale is disconnected from the PC, during
booting the hang (described above) does not occur and
programs can connect to the port without a problem when
the scale is plugged back in.

- have tested using 3 different machines and tried
different ports on each machine as well. Machines all
have latest service packs and patches. These scales have
been used with Win95/98 machines for a number of years
without a problem.

tia

 

[Chris Kusmierz]

Have a problem with a serial device (a scale) that, when
plugged in when booting up Windows, prevents any program
from connecting to the port once booting has completed.

Symptoms are as follows -

- scale device streams data continuously to the port (i.e.
there is no prompted input). Connection is at baud rate
9600. Scale does not make allowance for hardware flow
control.

- when the scale is connected to the PC, during booting
the mouse and keyboard devices will hang for about 10
seconds around the login screen.

- when the scale is disconnected from the PC, during
booting the hang (described above) does not occur and
programs can connect to the port without a problem when
the scale is plugged back in.

- have tested using 3 different machines and tried
different ports on each machine as well. Machines all
have latest service packs and patches. These scales have
been used with Win95/98 machines for a number of years
without a problem.

tia

WinXP has been known to detect some serial devices as plug-and-play serial
pointing devices.

Check in device manager for the presence of serial pointing devices, and
check which comm port they are using. If you find one, click properties and
choose disable. If you delete it Windows will re-install it.

HTH
Chris

 

[jh]

thanks for the help - you were spot on. that put me on
the following track to find this kb article -

283063 - Serial Device May Be Detected as a Serial Mouse
in Windows 2000

thanks again...