Device "PCI Simple Communications


Nov 11, 2015
Trying to get the qemu agent working for my Windows 2012 R2 VM's


Problem is that in my VM, in the Device Manager, there is no "PCI Simple Communications Controller"

I have installed all the virtio drivers, and there are no unknown devices showing in Device Manager, I am using the virtio disk and network devices without any issue.

What does the Device Manager device look like AFTER the driver is installed, and where does it appear within the Device Manager tree of devices (this screen-shot might be helpful to add to the wiki page). Maybe Windows already installed the virtio driver for me, but the device got renamed?


New Member
Aug 30, 2018
I'm experiencing the same on both, a Windows 10 and a Windows 8.1 client. I also installed all of the (now) most recent virtio drivers and tried some qemu agents (from newest to some older) with no positive results.
Did you get a solution for your issue?


Proxmox Retired Staff
Retired Staff
Oct 1, 2014


Aug 14, 2017
I have the same issue.
I enabled QEMU Guest Agent for the VM, installed the mention version you have shown above into the guest, but the Agent does not work.
I also cannot do the step mentioned for the driver as i do not have a "PCI Simple Communications Controller" in my hardware list. Any ideas?

Nevermind. As soon as you install the QEMU-Agent, the "PCI Simple Communications Controller" will appear in the list, it's not there before the installation as described in the wiki, though.


Nov 11, 2015
Follow-up on my original post, this is working. As wolfgang wrote, enabling first in Options Qemu Agent and then booting the VM... then device now shows up. We have done multiple Windows VM installs (Server 2012r2, Win7, Win10, Server 2016) now it works great.


Jan 28, 2020
Republic of Ireland
Just to update this, as I don't think the full process is very clear and hopefully the Wiki can be tidied up:

First you need to install the guest agent. This is available in an ISO from Fedora. This in itself is a shade obscure - starting:

Then under "Windows OS support":

Then under "Direct downloads" is the link to the full ISO:

Download that to your administrative desktop. Then in Proxmox you need to upload that to your local storage using the [Upload] button within "Contents". Once uploaded go to the hardware within your Windows Guest and mount the virtio-win.iso to the cdrom of that guest.
Then install the qemu-ga-x64.msi (64-bit) or qemu-ga-x86.msi (32-bit) from the mounted iso in the guest. You could get the msi to there from downloading within the guest or copying it over via other means - doesn't matter. But you're gonna need a further driver off the ISO anyway so I just went with mounting that.

Now this is the bit I missed initially, you've to shutdown your guest _before_ going into Options of the guest and enabling the checkbox for "QEMU Guest Agent". The vm has to be off for this to take effect - setting whilst booted and rebooting won't work.

Once that's done then you can boot the vm from cold then open Device Manager in the guest and the "PCI Simple Communications Controller" shows up. Then install the driver from driveletter:\vioserial\"OSversion". I'll prompt to trust the Redhat signed driver etc.

It doesn't seem to need a further reboot after that's installed, the Summary screen for the VM shows guest agent info under the IP information successfully.
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