Running Multiple Operating Systems
Why Multiple OSs?
There are several reasons for running either a dual-boot or multi-OS computer, including:
- You want to run a “gaming machine” as well as a “business machine” on the same computer but don't want to endanger your business installation.
- Web designers want to view their work on various operating systems using their native web browsers.
- A piece of legacy hardware, such as a scanner, works on Windows XP, but not in Windows 7.
- IT staff may need to be able to work with older as well as new versions of Windows.
- You want to experiment with an operating system like Linux, but need to be able to use Windows as your main operating system.
Games are the number one reason that many folks continue to run Windows as their operating system. As games move to Java and other cross-OS technologies, the need for Windows diminishes, but not for the most intense of these games. What if you could run your games in a Windows environment?
What if you could run the operating system of your choice in parallel with your current Windows setup? This page discusses the various options for doing that.
There are several options discussed on this page. I'd recommend choosing the solution that requires the least effort on your part (unless you like experimenting and aren't risking critical data in the process).
Several terms are used (sometimes incorrectly) to describe the option of running more than a single operating system on one computer. I'm going to use the following two terms:
- Dual boot: running more than a single version of the same operating system (i.e. Windows XP and Windows 7)
- Muli-OS: running more than a single operating system (OS) on a computer (i.e. Windows XP and Linux).
Backup Your Data!
You should backup your data in case something does go wrong during any of the procedures on this page. It is strongly recommended that you make routine backups because hardware failures, viruses and other disasters happen — not to mention human error.
Windows 8's Secure Boot Defeats Linux Installations
Users wanting to install Linux onto a preinstalled Windows 8 system will have difficulties because the new Windows uses UEFI instead of BIOS to enable the Secure Boot technology because the Linux installer is treated like a virus.
- Matthew Garrett has developed a Secure Boot bootloader which will allow you to install Linux (shim.efi).
While this issue came to my attention because of issues with Linux installs, it could affect any attempt to create a multi-boot environment.
Experienced Users Only
Running multiple operating systems on one computer requires advanced knowledge of how computers work, including how the OSs you wish to work with interact with each other. You'll need to know:
- how to partition your drive to accommodate the various OSs;
- the requirements of file systems involved;
- the ability to work with advanced installations;
- how to share data between installations; and
- at least a basic understanding of the various components involved in today's computers.
Potential Compatibility Issues
The fact that you can share the hardware means a savings of the cost of the hardware as well as the amount of space you can dedicate in your working environment for multiple computers.
However, there are potentially some compatibility issues, particularly when running multiple OSs. You'll want to check for the availability of drivers for the operating systems that you want to run for your particular hardware. This is particularly important for legacy operating systems (those no longer supported with newer hardware) and with newer operating systems (which may only offer beta drivers or perhaps none at all for your hardware).
If you need to share data between the various operating systems, it gets more complex because you're forced to use the lowest common denominator in terms of what file systems are used — at least on the data partition or drive. Such choices can compromise your data because older file systems like FAT are not as stable as NTFS and cannot see larger drives (partitions) without special utilities.
Some Resources Outdated or Assumptions Invalid
Some of the resources on this page are outdated (particularly the links) but are included because they provide general knowledge and often are useful if you want to run an older OS. Some of the assumptions may no longer be valid. It is best to view as much about the knowledge you are seeking as you can find. Between these various articles you will begin to get a sense of what is right for you and what is accurate for today's hardware and software.
Aimed at Windows Users
The information on this page is generally aimed at Microsoft Windows users, contains information and resources for other operating systems. The Multiple Operating Systems in the OS/2 Resources section is older, but may have information valuable to those wishing to multi-boot OS/2 or ECS.
If you are unsure of what is being discussed, you should consult someone with the necessary experience. If you are contemplating more than one operating system, be sure the person understands both operating systems, particularly if you have existing data or other software to protect.
If you do install a version of Windows no longer supported by Microsoft or any other obsolete operating system (without the current service packs and updates) you should be aware that you're placing your computer at greater risk of security breaches, malware and viruses if the computer is connected to the Internet. This places all your data at risk if you're sharing it between various installations.
Before you attempt to install a dual- or multi-boot environment, you might want to try out one of the software solutions that run alternative software in a separate “virtual environments.”
As hardware has improved beyond the actual requirements of the operating systems they support, it becomes possible to share resources with another separate OS. Remember, this assumes that you're not running an older computer that barely supports the existing installation.
There are several options to run Windows programs on other operating systems and vice versa. Be sure you don't opt for a solution that is too complex or expensive and that your computer can meet the performance requirements.
- Oracle's VirtualBox is strongly recommended for running multiple virtual systems on Windows.
- Windows Virtual PC is Microsoft's solution for running virtual XP on Windows 7 Professional and Windows 7 Ultimate.
- Parallels allows Mac users to run Windows applications.
- WINE allows users to run Windows applications on Linux, BSD, Solaris and Mac OS X.
Dual Booting Windows
A feature of Windows XP has been the ability for it to allow for an existing legacy Windows system for coexist with it, particularly if the existing version of Windows is already installed when you install Windows XP. As you move forward in Windows versions, you move away from DOS and closer to virtual systems that may not allow older programs to run natively. Dual booting can give you the option to run an older version of Windows to allow such programs to run.
Earlier versions of Windows doesn't necessarily recognize the settings of later version, so you're best to install the earlier Windows version first then proceed to the more recent. If they corrupt the boot settings or other critical files, your computer may not start at all or may not recognize the newer operating system.
Try Compatibility Mode First
Windows 7 has the ability to run in compatibility mode as far back as Windows 95, in 256 colours, 640 x 480 resolution and more. You might want to give this a try before attempting to create a dual-boot install.
Don't Mix Windows Versions
Installing a second version of Windows in the same partition will mix the contents of the two versions of Windows, possibly overwriting key files. Use separate partitions (I'd recommend separate hard drives, if possible) so that the resources are not intermingled.
Windows 7 and Vista Windows 9x (95, 98, 98SE & ME — although only Windows 98SE is practical) has a very different way of handling many files than XP does, including “user” folders such as My Documents.
- Windows 95 introduced My Documents, but it was located in
C:\My Documents. This file could be moved without creating issues in Windows 98.
- Windows XP introduced multi-user installations as a default, moving My Documents to
C:\Documents and Settings\[user name]\My Documentsand creating All Users for settings and documents shared between users. You could still move the My Documents to mimic Windows 95, but you risked creating problems if a second user was added to the computer.
- Windows Vista changed Documents and Settings to the simpler Users and My Documents was now located in
C:\Users\[user name]\My Documents. Instead of My Documents on the desktop, the User's folder appeared, containing My Documents as well as moving the My Music, My Pictures, etc. from My Documents into the User's folder. The All Users became Public.
Other important changes made in Vista (and Windows 7) were to move the location of the Application Data folders and to reclassify them under Local, LocalLow and Roaming (with the majority of application using the Roaming to allow sharing between computers as well as between users).
Sharing With Different Windows Versions
Windows 7 and XP should be run on the NTFS file system, but if you want to be able to see the information on these partitions from Windows 9x you'll need to use Fat32. There are great advantages to NTFS, including the ability to handle much larger drives, automatic compression and improved file features, such as private folders. Unless you need to see and dynamically alter the information on the Windows 7 or XP partition when booting to the Windows 9x installation, I'd use NTFS.
If you choose NTFS, Windows 9x will be unable to "see" the Windows 7 or XP drive. You'll have to share documents with one of several methods, including:
- A common drive or partition formatted with the FAT32 file system. This can be either an internal drive or an external USB drive.
- A USB thumb-drive (you'll need to install drivers for Windows 98SE). This works if you seldom share information.
Obviously, this has limitations if you are going to be continually sharing dynamic information and it will be impossible to share programs.
Windows 9x Least Flexible
Windows 9x demands the C: primary partitions) and is a predatory operating system that will try to write data into any drive or partition that it can read (FAT16 in particular). It will offer to format anything it cannot read (such as NTFS or HPFS) if it can "see" it.
For this reason, I'd suggest using an older PC to run these older versions of Windows. If your programs need direct DOS hardware access, you can create serious issues in dual-booting newer versions of Windows. A Virtual Environment install might be a better solution.
Install Programs on Both Versions of Windows
You will need to install the programs in both versions of Windows, so that the correct information is written into the Windows Registry for each operating system, even if you are sharing the program data.
HyperOS gives you instantly available spare cloned Windows systems which you can switch to with a double click. The Geek version runs up to 10 Windows systems from your boot drive and up to 10 more (one per partition). The SuperGeek version upgrades this to 24 partitions. Each active partition becomes the C: drive — required by Windows base files and some other software. Read the site's description for more information.
Dual Booting Resources
- Install more than one operating system (multiboot) in Windows 7
- How to create a multiple-boot system in Windows XP
- Multibooting in Windows XP Made Easy
- To specify the default operating system for startup
- Dual Boot Windows XP Tips! from WinXpFix.com
- Multiple operating systems and file system compatibility
- Deciding Whether a Computer Will Contain More Than One Operating System
- Installing more than one operating system on your computer
- Choosing a file system: NTFS, FAT, or FAT32
The Multi-OS Environment
About IBM OS/2 and ECS
There is multi-OS information more relevant to OS/2 or eCommStation users in the OS/2 Resources Section, although much of the information is quite dated compared to what is on this page.
OS/2 and eCommStation provides a stable and work-friendly business operating system which wins over those that take the time to learn its advantages. However, the ability to play games and support for much hardware and accessories is either unavailable or not as advanced.
You can use various hardware devices to enable you to boot to alternative operating systems. The advantage is that you don't have to worry about one operating system damaging the information or file systems in another operating system's partition. The disadvantage is that it is impossible to share data and/or programs because they are physically separated.
Removable Drive Bays
Since the price of hard drives has come down significantly, you can purchase a removable drive bay that can be easily swapped for your various OSs. Note that you should be sure to purchase the same brand and model of drawer if you wish to leave the hard drives in the bays and ensure that the correct drawer is purchased if you are running ATA66 or better drives.
If your need for changes is infrequent, you might consider simply swapping the cables inside your computer when you need to switch operating systems. This requires you to open the computer case and is not an option for laptops, but the only cost is the price of the additional hard drive(s).
Note that newer computers continue to have power when they are shut down. Be sure to remove the power cable from the computer and ensure external devices and the monitor are turned off (a common power bar works great for this).
You might try changing the boot sequence in the BIOS to boot to a different drive or to enable/disable SATA and IDE drive options. This should only be contemplated if you understand the BIOS and can comfortably experiment with this option.
There are various boot manager program that dynamically will allow you to switch between various operating systems. These program can “see” various types of file systems and usually provide some sort of a boot menu that intervenes in the normal bootup of your computer so that you can make a choice.
- zBoot Manager.
- Power Boot is a utility that allows you to install and run multiple operating systems without the restrictions that others like Boot Manager and CtrAltDel Commander impose such as the ability to place an OEM version of software that checks for other operating systems before allowing a new installation (e.g. Windows 9x).
- One of the oldest is System Commander from V Communications. System Commander allows up to 32 Operating Systems in a DOS partition or each in their own primary or logical partition. You might wish to read the review of System Commander Deluxe by Walter F. Metcalf.
Partitioning Your Hard Drive
Backup Before Partitioning
You should backup your data in case something does go wrong during any of the procedures on this page. It is strongly recommended that you make routine backups because hardware failures, viruses and other disasters happen, not to mention human error.
Create One or More Partitions
A single hard drive can be formatted with one or multiple partitions. The first (or Primary) partition is made active (bootable) and any other partitions are grouped into a Logical partition.
In Windows, each of these partitions are assigned a drive letter by Windows, if it can “see” the file system on that partition, and ignored if it can't. Whether or not a particular file system can be seen depends upon the version of Windows and if there are operating systems other than Windows installed.
The traditional tool for creating and deleting partitions is FDISK — a command-line utility relic from DOS.
However, you can boot to the Windows XP installation CD on most computers, then create or delete NTFS or FAT32 partitions. If you delete or format a partition, it will erase all information on that drive.
Windows 7 Disk Management
Use Windows 7's built-in disk management software (right-click My Computer and left-click Manage then select Disk Management). You might be unable to see a drive if you are using several USB drives on multiple systems. Run the Disk Management to create a different drive letter for each drive.
One tool that you will find useful in setting up multiple operating systems is Partition Magic (now owned by Symantec). You can create and modify partitions without destroying the data although you are advised to backup the data in case something does go wrong during the process. The newest version works only in Windows.
The image above shows a FAT32 C: partition labelled WIN98 and a Logical partition that contains two FAT16 partitions (D: and E:). While this image shows an older system with FAT32 and FAT16 partitions, modern Windows systems are more likely to contain only NTFS partitions.
Beware of Possible Gottchas
If you are running Partition Magic in Windows, it may offer to "fix" partitions on a multi-OS system. Because not all operating systems create partitions the same way, this can make destroy partitions containing other operating systems such as OS/2. If this happens, you'll not be able to recover the data on those partitions.
MiniTool Partition Wizard
MiniTool Partition Wizard Home Edition is a free partition manager software that supports 32/64 bit Windows Operating System including Windows XP, Vista, Windows 7 and Windows 8.
Home users can perform complicated partition operations by using this powerful yet free partition manager to manage their hard disk. Functions include: Resizing partitions, Copying partitions, Create partition, Extend Partition, Split Partition, Delete partition, Format partition, Convert partition, Explore partition, Hide partition, Change drive letter, Set active partition, Partition Recovery.
MiniTool Partition Wizard Professional Edition is required in a business environment.
Gnome Partition Editor is a Linux solution, but Windows users can use GParted Live by booting from another device like a USB thumb drive or a CD-ROM. Because it is open source, it is free to use.
- General Information on Starting Multiple Operating Systems
- Multiple Operating System Setup
- Das Boot ("Getting the boot") is dated 1995 but has some good basic information about how various operating systems work and how you can get them to work together.
- Managing Multiple Operating Systems HOWTO is a useful resource for those wishing to run multiple OSs with Linux.
- Windows Virtual PC.
There are numerous file systems, many of which are specific to one or more operating systems. Because they handle information in different ways, they each have advantages and disadvantages. As file systems age, their limitations increase, much like the limitations of the operating systems they run on.
For the most part, the differences are transparent to the average user, except during installation — if choices between two or more file systems are offered.
Various PC File Systems
The more common PC file systems are shown in the table below (in order of increasing superiority):
|File System:||Description:||Used By:|
|FAT16||File Allocation Table (16-bit)||DOS, Windows 3x, 95, OS/2, digital cameras|
|FAT32||File Allocation Table (32-bit)||Windows 95B, 98, Me and XP|
|NTFS||New Technology File System||Windows 2000, XP, Vista and 7|
|HPFS||High Performance File System (16-bit)||OS/2 and early NT4|
|JFS||Journal File System||OS/2, eCS|
|Ext2/3||Extended File System||Linux|
|WinFS||Windows Future Storage||Not used|
Other File Systems
Of course, there are many other file systems and the comparisons are interesting. Don't forget to take into account the age of the file system. Older technology is not going to have the hind sight available to newer releases.
- Microsoft's Overview of FAT, HPFS, and NTFS File Systems
- DOS FAT 12/16/32, VFAT
- File systems (FAT, FAT8, FAT16, FAT32 and NTFS)
- New Technology File System (NTFS) has interesting history, but is somewhat cluttered by ads at the top.
- NTFS compared to FAT and FAT32
- NTFS and FAT File Systems Explained
- High Performance File System
- Overview of the JFS file system.
- File systems HOWTO by Martin Hinner documents how to see other file systems (including HPFS and OS/2 LVM) from various operating systems, including NT4, DOS and Linux.
- The Linux File system.
- List of Linux File systems, Clustered File systems.
In many cases, operating systems can use multiple file systems and your choices to use one over the other might include security concerns, data reliability, speed of access, backwards compatibility with earlier systems or any number of other reasons.
Can You See Me?
Operating systems generally cannot “see” the file systems for which they were not designed (at least not without third-party utilities). For example, Windows 98SE would not be aware of an NTFS partition, but would see and be able to work with files on either FAT32 or FAT16 partitions or drives. Generally, Windows can see the file systems for the versions prior to the version you're using.
Prepare for Multi-OS Installs in Advance
One caveat: You should set up the partitions prior to installing the operating system(s) since adding or changing the file system can alter the drive lettering as it is viewed by the various operating systems. Operating systems beyond the C: partition might not be able to boot or if they boot may be unable to locate programs on other partitions.
August 3, 2013
Removed link to kBootManager (http://macarlo.com/kbm.htm) as it no longer appears to be live.
May 6 & 27, 2013
Updated to include more information about Windows 7 and to warn about earlier versions overwriting boot settings in newer versions of Windows. The warning about the expired HyperOS security certificate was removed.
February 22, 2013
Updated to include information about HyperOS.
January 5, 2013
Updated to include information about Windows 8 and to reorganize content on the page.
August 18, 2012
The most recent updates included changes from an assumed base of Windows XP to an assumed base of Windows 7.
May 27, 2011
This page was created based upon the information found in the OS/2 Resources section of this site to update it and make it more relevant for Windows users.
Updated: August 3, 2013