1. Shut down the VirtualBox VM
2. Copy the VDI file to the Proxmox PC using rsync
3. Create a new VM in Proxmox with all desired parameters, but DO NOT select an installation medium. Graphics card: SPICE
4. Log in to Proxmox using ssh and navigate to the directory with the VDI file
5. Run qm importdisk 100 windows-server.vdi storage_pool (replace '100' with the VM number, “storage_pool” might be something like “local-lvm” for you)
6. In the Proxmox GUI, under VM 'Hardware', a new disk will appear, assign it to SATA-0, unmount and delete the old one (SCSI)
7. In the Proxmox GUI, under VM 'Hardware', add up to five USBs if needed, Type: SPICE
8. In the Proxmox GUI, under VM 'Options', change the boot order so that the new SATA-0 boots
9. Click start and the imported VM will start.

1. Import the ISO file into Proxmox as follows
2. In the Proxmox GUI, under local(pve) - ISO Images, use the Upload button
3. Create VM, in the OS tab, the uploaded ISO will be available

1. In the Proxmox GUI, under VM 'Hardware', add up to five USBs (depending on simultaneous need), Type: SPICE
2. On the workstation: install the “virt-viewer” package
3. In the Proxmox GUI, with the VM running, select SPICE from the “_Shell” listbox, this will save a .vv file
4. On the workstation: open remote-viewer xyz.vv, the VM will now be displayed
5. In the Remote-viewer menu “File”, select USB Devices, choose the desired USB Device, and it will be passed through to the VM

1. Shut down the VM
2. Connect the USB device
3. In the Proxmox GUI, under VM 'Hardware', add a USB, Type: Use USB Vendor/Device ID, select the new device
4. Start the VM

1. On the switch: mark the VLAN as “tagged” on the corresponding ETH port (in addition to the normal “untagged” or “native”, as this is needed, among other things, for the Proxmox GUI)
2. In the Proxmox GUI, under pve - System - Network, open the bridge and activate “VLAN aware”
3. In the Proxmox GUI, under VM - Hardware - NetworkDevice, open and enter the VLAN Tag
4. In the VM, set the correct IP range

Windows VMs can be installed, but as usual with Windows, they lack many drivers, especially for the network to function. The appropriate drivers can be found here: DRIVER DOWNLOAD (Source: GitHub)

1. Unpack the ZIP file
2. Copy the ISO file to a storage in Proxmox

In the Windows VM, select: “Hardware” - “CD/DVD” and specify the ISO file. This makes it available under Windows as a CD drive These drivers were missing for me:

1. NetKVM: select the Windows version and platform, right-click the *.sys file and choose “Install”
2. Balloon: select the Windows version and platform, right-click the *.sys file and choose “Install”
3. Open Device Manager, there is still a driver missing. Click on it, choose “Update Driver” and let it search through all packages

Steps 1 and 2 CANNOT be done with Device Manager, they must be done exactly as described! After that, all drivers were installed for me.

For this, the following must be installed:

qemu-guest-agent and spice-vdagent

Additionally, the kernel should be up to date.