Try v6.0.24 or earlier.

https://www.virtualbox.org/wiki/Changelog
https://www.virtualbox.org/wiki/Download_Old_Builds_6_0

VirtualBox 6.1.0 (released December 10 2019) […]
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VirtualBox 6.1.0 (released December 10 2019)

This is a major update. The following major new features were added:

Implemented support for importing a virtual machine from Oracle Cloud Infrastructure
Extended support for exporting a virtual machine to Oracle Cloud Infrastructure, allowing the creation of multiple virtual machines without re-uploading. Also added option to export a VM to the cloud using the more efficient variant "paravirtialized", and to specify free-form tags for cloud images
Virtualization core: Support for nested hardware-virtualization on Intel CPUs (starting with 5th generation Core i, codename Broadwell), so far tested only with guest running VirtualBox
Graphics: New style 3D support (with VBoxSVGA and VMSVGA) remains, old style 3D support (with VBoxVGA) has been completely removed
Shared Clipboard: Implemented experimental support for file transfers (Windows hosts/guests only at the moment). Needs to be enabled via VBoxManage (disabled by default).
In addition, the following items were fixed and/or added:

Virtualization core: Drop recompiler, i.e. running VMs now needs a CPU supporting hardware virtualization

Vmware Player may work as well:
VMware-player-12.0.0-2985596.exe

DepthsDoes wrote on 2021-03-21, 20:53:

CPU: Pentium Dual CPU E2200 @ 2.20GHz

This is a 2007 CPU and indeed it does not support VT.

kjliew wrote on 2021-03-22, 05:01:

DepthsDoes wrote on 2021-03-21, 20:53:

CPU: Pentium Dual CPU E2200 @ 2.20GHz

This is a 2007 CPU and indeed it does not support VT.

Right, but age alone is not the main problem, it's the CPU/BIOS combo.
Some CPUs do support intel vt or amd-v, but the BIOS gets in the way.
Not seldomly, that totally confuses the VM software.

In older versions of VMware, VirtualBox, MS Virtual PC that Hardware-virtualization was optional..

In case of VirtualBox, the 2.x/3.x series are compatible with AMD K9 and comparable intel processors.
The early 4.x series may also be fine with such older processors..

I've run VBX 4.1.14 (r77440) on a Mac OS X compatible, with Core2Duo processor, I think.

https://www.youtube.com/watch?v=c6e3FzI9Tuw

VirtualBox v5 is said to be incompatible with lots of stuff currently (ReactOS ezc), so better avoid that.

Anyway, hardware-virtualization is not always best for compatibility/stability.

From what I remember when using Virtual PC 2007/AMD-V:
Windows 3.11 needed it for Win32s
Windows 98SE got totally unstable
OS/2 also was affected.Not sure how, though.

In DOS VMs, it sometimes was helpful, sometimes it made applications crash.
Using EMM386 helped a lot, because it ran in V86. I assume, this avoided using Virtual PC's internal Real-Mode handling mechanism (emulation core? hacky virtualization?).

No, if you had Intel CPUs back then, Intel deliberately did this to differentiate price segment. The Celeron and Pentium did not get VT, only the Core. It had nothing to do with BIOS. Later, even certain Core models won't have VT. In the post-Nehalem era, some "K" unlocked CPUs also did not have VT.

However, the pre-Nehalem Intel VT, even if the CPUs have it, is pretty much useless today due to lacking support of SLAT.

That CPU does not support any hardware virtualization, no matter what, you will never be able to use VBOX on that machine.
https://ark.intel.com/content/www/us/en/ark/p … 00-mhz-fsb.html

Is there a reason that you really need running a machine with DOS as the main operating system?
You can install a real DOS on a separate harddrive (or wahtever spare storage device you have) and you can boot from that drive, if you really need to use a real DOS.

Or just simply use DOSBox.

Rencer wrote on 2021-03-22, 17:45:

That CPU does not support any hardware virtualization, no matter what, you will never be able to use VBOX on that machine. https […]
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That CPU does not support any hardware virtualization, no matter what, you will never be able to use VBOX on that machine.
https://ark.intel.com/content/www/us/en/ark/p … 00-mhz-fsb.html

Is there a reason that you really need running a machine with DOS as the main operating system?
You can install a real DOS on a separate harddrive (or wahtever spare storage device you have) and you can boot from that drive, if you really need to use a real DOS.

Or just simply use DOSBox.

I'm trying to install OS/2 Warp 4, Lindows (a Linux distro from like, 2004 or smth), and DOS with Windows 2.

kjliew wrote on 2021-03-22, 07:10:

No, if you had Intel CPUs back then, Intel deliberately did this to differentiate price segment. The Celeron and Pentium did not get VT, only the Core. It had nothing to do with BIOS. Later, even certain Core models won't have VT. In the post-Nehalem era, some "K" unlocked CPUs also did not have VT.

However, the pre-Nehalem Intel VT, even if the CPUs have it, is pretty much useless today due to lacking support of SLAT.

Hi, it seems there is a misunderstanding. 😅
What I said was general statement, it was not mot ment to be related to the Pentium Dual CPU E2200.

And yes, from what I know, BIOS support (or the lack of it) often is an issue.

https://2nwiki.2n.cz/pages/viewpage.action?pageId=75202968

https://bce.berkeley.edu/enabling-virtualizat … ur-pc-bios.html

nvm i got 6.0, it works.

DepthsDoes wrote on 2021-03-22, 18:27:

I'm trying to install OS/2 Warp 4, Lindows (a Linux distro from like, 2004 or smth), and DOS with Windows 2.

I just thougth, you only need to run something under DOS .
So you want not just runnig DOS programs, but running many different OS on that machine...
Well, good luck with it.