VirtualBox

Running Windows XP in VirtualBox is an easy to get started with XP without having to worry about hardware drivers (all provided with the guest additions) and also being able to run it in a more secure host environment.

Hardware virtualization
VirtualBox 6.1 requires hardware virtualization (VT-x) to be enabled. For older computers you now need to use an older version of VirtualBox and you will only be able to run 32-bit operating systems. it must be either 6.0 for Older systems or 5.2 for 32 Bits systems. 3D acceleration is no longer supported in VirtualBox 6.1 and newer.

Guest additions installation bug
Due to expiring certificates Windows XP guest additions won't install without disconnecting the virtual ethernet cable while installing.

Windows Xp as Host Operating System
The last version to officially work on Windows XP is 4.3.40. However inofficially it is still working, e.g. version 5.2.42 still works. If somebody is having problems with the older version, it is definitely recommended to try this or the newest 5.2-version. (Note: When updating, it is not necessary to shut down the Virtual Machines, however when going back to the older version one should shut down the VMs, otherwise the state probably cannot be restored)