Short tip: Windows 10 VMs under QEMU/KVM
Although there are now fewer and fewer reasons to use Windows for classic application programs, the Redmond operating system is unfortunately still needed, especially for supposed "enterprise software".
The installation of the operating system is quickly done thanks to virt-install or virt-manager. For screen resolutions higher than 1920x1080, it is recommended to configure the QXL type graphics card. This also supports an automatic adjustment of the screen resolution (as offered e.g. in virt-manager). The Windows SPICE Guest Tools are also required for this.
WHQL-signed drivers are available here, or from the Fedora project.
However, it is important to note that for QEMU versions before 7.2 (before Proxmox VE 7.4) no German ISO image may be used. There is a bug here that affects network traffic. Network cards can be configured, but not used. In the device manager only the following error message appears:
1Error code 56: Windows is still configuring the class configuration for this device
The problem affects all editions of Windows 10 and applies to all network card types (e1000, rtl8139, virtio). The bug is discussed in the Proxmox forum, among others:
With English ISO images this error does not occur - many thanks to datavizzard for the tip!
English ISO images are available from the Microsoft Evalution Center - German localization can be retrofitted via language pack. This is a change from older Windows versions, where either localized images had to be used or language packs were reserved for the Enterprise version.
More information about Proxmox is available in this FOCUS ON: Linux episode