Windows guest cannot connect to COM1 (virtual serial port)

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kestrel.mond
Posts: 1
Joined: 11. Jun 2010, 13:50
Primary OS: Mac OS X other
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Windows

Windows guest cannot connect to COM1 (virtual serial port)

Post by kestrel.mond »

To be clear, and to differentiate from all the other posts on the forum, I am NOT using any sort of USB to serial device. I'm just talking about setting up a plain jane virtual serial port, which I want to use to try and do kernel debugging between two windows VMs (I've successfully done this in the past with various versions of VMWare, and now I want to stop using that on a PC and start using virtualbox on my mac.)

Before starting up the Windows guest, I go to the configuration, and select serial ports.

I check "Enable serial port" and select Port Number COM1 with it's default options. The port mode is set to "Host Pipe" and I check the box "Create Pipe". I then set the pipe path to be /Users/kestrel/bla. When I start up the VM, I can see it IS creating the pipe on the host system ("srwxr-xr-x 1 kestrel staff 0 Jun 10 13:21 bla")

When the system is booted, I right click on My Computer and select Manage. Then I select Device Manager. Under "Ports (COM & LPT)", it lists only LPT 1. It should also be listing COM1, but it isn't.

I right click on ports, and select "Scan for hardware changes" but nothing changes. I then go to Control Panels and select Add Hardware. Since there's no COM port option, I select the last, generic, option: "Add new hardware device." I then select "Install the hardware that I manually select from a list". I then select "Ports (COM & LPT)" and then "Communications port". It subsequently says "The software for this device is now installed, but may not work correctly. Windows cannot determine the settings for this device. Consult the documentation that came with this device and use the Resource tab to set the configuration. (Code 34)"

I then go back to Device Manager, and see COM3 listed, but it has a little yellow "!" icon displayed, indicating it's probably still having problems.

When I then open up WinDbg, and try to connect to any port, com1, com2, or com3, in all cases it says it can't find the port.

I also tried going back out and reconfiguring the virtualbox settings for the VM to tell it to use COM3, but I was still unable to connect to it with windbg.

Has anyone set up a virtual serial port such that it can be connected to from within the Windows guest?

Thanks

Kestrel
xcr33d
Posts: 1
Joined: 7. Jul 2010, 09:13
Primary OS: PCLinuxOS
VBox Version: OSE other
Guest OSses: Windows XP

Re: Windows guest cannot connect to COM1 (virtual serial port)

Post by xcr33d »

Hi,
I had the same problem. my host is Slackware 13.1 and as guest Windows XP. I did what this post said: http://www.virtualbox.org/ticket/1273
Here is the important part:
Control Panel, Add Hardware

...

Yes, I have already connected the hardware: selected

Add a new hardware device (last on list)

Install the hardware that I manually select from a list: selected (skips useless search by Windows)

List all Hardware

Standard port types: Communications Port

Device Manager showed this created COM3, with a problem (address and IRQ not known).

Control Panel, Add Hardware

...

Yes, I have already connected the hardware: selected

Add a new hardware device (last on list)

Search for and install the hardware automatically: selected

Windows found a Communications Port

...

This created COM1. COM3 uninstalled.
I activated the two ports that de VB supports and both of them work.
I hope its no too late

Edson
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