Attaching to host serial port on Windows 7: Permission problem

[Steve Weidman]

I am attempting to pass the RS-232 serial ports of the host operating through to the guest operating systems. I have fully functional COM1 and COM2 ports available and working in the host system. Serial Ports are set up in the guest operating system as Port 1, COM1, Host Device (COM1) and Port 2, COM2, Host Device (COM2) When I attempt to "map" these devices to the guest operating system, I receive the following error:

"Failed to start the virtual machine (Windows 7 RC, Windows 98SE and Windows 95C report the same error). Cannot open host device 'COM1'for read/write access. Check the permissions for the device. (VERR_ACCESS_DENIED). Unknown error creating VM(VERR_ACCESS_DENIED). Details: Result Code: E_FAIL (0x80004005) Component Console Interface: IConsole {0a51994b-cbc6-4686-94eb-d4e4023280e2}"

The only way for the guest systems to start is to "disconnect" the serial ports.

Host System Details: Windows XP Pro, Version 2002, Service Pack 3 Intel Pentium 4, 3.00GHz 3.00GHz, 3.5GB of RAM COM1 I/O 03F8-03FF, IRQ 04 COM2 I/O 02F8-02FF, IRQ 03

VirtualBox 3.0.6 r52128

[Steve Weidman]

Update:

I tried the same setup on the Kubuntu side of the system and it works flawlessly. This seems to add more evidence that it's either a Windows XP problem or a VirtualBox for Windows problems.

Host Details: Linux ubuntu 2.6.28-15-generic running KDE 4.2.2. VirtualBox for Linux 2.1.4-OSE Serial Port 1, COM1 Host Device (/dev/ttyS0) Serial Port 2, COM2 Host Device (/dev/ttyS1) Same guest operating systems (Windows 7 RC, Windows 98SE and Windows 95C)

[Frank Mehnert]

This might be a problem which started with Windows 7.

[Steve Weidman]

I updated VirtualBox to the latest version 3.0.8. The problem is not only in Windows 7, it is in all guest systems...none of them can see the windows xp host serial ports.

[Prudentman]

About this defect, I have an opinion different from Permission problem. When I set Serial port as /dev/ttyS0 (My guest is Ubuntu), the error message will show "Failed to open host device "\dev\ttyS0" (VERR_PATH_NOT_FOUND)". So I think it might be has another problem.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.