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Windows 7: COM1 (I/O conflict ? ) Port

19 Jun 2018   #1

windows 7 Professional x64
COM1 (I/O conflict ? ) Port


Like a long time ago, I am afraid I have another machine with a COM1 port not working


1) I Installed a printer, with generic text /generic driver
at COM3

2) Then I changed it to COM1 because the hardware has unmarked ports#
and the external device has to be that one.

3) I altered the port settings as usual, from 9600 baud to a higher 19200 baudrate.

After some test prints, it doesnt work thou...
The "com1" is unavailable when checking
Then the printer/unit was removed from system.
Installed a new
Still no success.



0x000003E8 - 0x000003EF - Communication port COM3 )
0x000003F8 - 0x000003FF - Communication port COM1 )

Is there a way to roll-back this?
How to show old /deleted printers and drivers?

My System SpecsSystem Spec
19 Jun 2018   #2

windows 7 Professional x64

Current status:

There is no printer anymore in my system, it doesnt show up in the Devicelist.
But I searched around in the registry, to found old entries that could be a problem

Searched: "printer x"


printer x [REG_SZ] (WINSPOOL,COM1:

(1) What to do? Delete it ?

I Also found one entry when searching for "COM1" in the registry:


printer x [REG_SZ] (WINSPOOL,COM1:,15,45
My System SpecsSystem Spec
27 Jun 2018   #3

Linux Mint 18.2 xfce 64-bit (VMWare host) / Windows 8.1 Pro 32-bit (VMWare guest)

If you have a serial printer, then you should try something like this to connect it to the computer:

It is a serial to USB adapter cable -- it will let you convert your printer from serial to USB. The only problem that people are having with this cable is that the two nuts on the serial end of the cable are permanently attached, and they might get in the way of your being able to connect your printer's serial cable to this cable. Make sure that is not a problem before you purchase this cable. In other words, make sure that your printer cable has screws, not nuts, on the end that plugs into the computer. And make sure the plug is the same size as the one on this cable - as I recall, serial can be a wide or a narrow plug. (This one is narrow.)

The traditional serial port that you have described above is old technology. My thought is that there are some incompatibilities with Windows 7 (a modern operating system) which are preventing it from working. On the other hand, if you can connect the printer as a USB printer, you will likely eliminate those incompatibilities.
My System SpecsSystem Spec

27 Jun 2018   #4

win 8 32 bit

Have you checked for IRQ conflicts in a lot of systems com ports are shared
My System SpecsSystem Spec

 COM1 (I/O conflict ? ) Port

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