Windows 95 installation

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Windows 95 can be installed directly onto a legacy x86 computer or in a virtual machine. Drivers needed to run hardware with Windows 95 can be sourced from surviving driver CD-ROMs, floppy disks or websites that archive old software. For installation into a virtual machine, VMWare typically provides compatible drivers. Windows 95 is not recommended for everyday use and should only be installed and used for niche situations. Windows 95 is not required or recommended for most computer users due to its age, unreliability and lack of security. Windows 95 is a vector for cyber attacks and as such must be isolated from production networks to reduce potential attack surfaces.

Phase 1: Determine feasibility

It is not recommended to install or use Windows 95 for most users. In general, most users will not require it and may find DOSBox a more viable option for running legacy software designed for MS-DOS. As such, the first phase is determine the feasibility of running Windows 95. Such a legacy operating system is almost 30 years old and was created long before modern security technologies were developed. As a such, Windows 95 is not considered secure even if compatible security software is installed. There is an increased risk of attack surface when installing Windows 95.

Windows 95 may be required if:

  • You need to run legacy software to access data stored within a database that remains in widespread use.
  • You need to run a legacy payment system to access data.
  • You need to run games that do not work with Dosbox but do work in Windows 95.
  • You are a researcher comparing different operating systems or are producing a documentary on Windows 95.

System Requirements

Windows 95 must meet these minimum requirements:[1][2]

Minimum Recommended Notes
System Memory 8 MB 12 MB
Disk Space 70 MB 666 MB Additional space might be needed for applications
Processor 386DX (20MHz)

These additional requirements are needed for running legacy games under Windows 95:

Minimum Recommended Notes
System Memory 64 MB 128 MB
Disk Space 2 GB 8 GB Varies according to requirements
Processor 386DX (20MHz) Pentium 1 (90 Mhz)[3]

Windows 95 will install on, but may not start on computers that have more than approximately 480 MB of memory.[4][5][6]

Phase 2: Bare metal vs virtual installation

Once you have determined that you must install Windows 95, the next phase is decide whether you will install it to a legacy computer (a bare metal install) or you will install it within a virtual machine. The advantage of a bare metal installation is guarrenteed full compatibility but it also comes with several downsides. For example, additional power needed to run the legacy computer and also potential security risks. For example, unlike virtualisation, it is increasingly difficult to isolate network traffic to/from the vulnerable Windows 95 computer. Conversely, a virtual machine often has a "NAT" option that can help isolate network traffic. Neither solution is secure on its own. Cyber attacks are possible with both solutions but the latter is slightly more secure by default.

It is not recommended to try and install Windows 95 onto a modern computer. Many of the computer's hardware compatibilities will not work and Windows 95 may fail to boot because of incorrectly detecting memory or other hardware parameters. Also, it wastes hardware resources because most of the memory will not be usable.

Emulation is a trade off between real hardware and virtualisation because it emulates legacy hardware that works nicely with Windows 95, but it requires time and resources to configure an emulation environment. This choice will also be impacted by the installation mediums that are available to you.

Phase 3: Booting Windows 95 installer

An original MS-DOS startup disk or Windows 95 floppy disks can be used to start the Windows 95 setup. By default, old computers will boot from a floppy disk if one is found in the drive.

  • If you have a Windows 95 optical CD-ROM, you may need to use an MS-DOS startup disk in conjunction with the CD-ROM to install Windows 95.
  • If you do not have an optical CD-ROM, but have Windows 95 data files on an ISO, or else where, you can create a Windows 95 CD-ROM using burning software.
  • If you own a Windows 98 boot disk, then you can use that boot disk to kick start the Windows 95 installation process.
  • Unofficial MS-DOS startup disks can be found online.

Windows 95 was typically installed from a series of 3 and a half inch floppy disks, or from a Windows 95 installation CD-ROM. If you own a Windows 95 CD-ROM, then it should first be converted to a disk image to mitigate wear and tear on a dated CD-ROM. Barring exceptional circumstances, Windows 95 CD-ROMs are not bootable like Windows 98 or Windows XP boot disks. This means that if you put a Windows 95 CD-ROM into your computer, or load a disk image in your virtualization software, the Windows 95 setup will not start. Generally, Windows 95 setup disks simply contain the data that is copied over to a hard disk when Windows 95 is installed.

Windows 95 and 98 CD-ROMs

  1. Insert the physical 3+12-inch (89 mm) floppy disk with the MS-DOS startup boot files into the floppy disk drive, or use a Windows 98 CD-ROM to boot into MS-DOS. The computer will try to boot from the MS-DOS startup disk. If prompted, select the option to start the command prompt. You do not want to install Windows 98 here.
  2. You should see the following:
  3. Insert the Windows 95 CD-ROM into the CD-ROM drive in the computer then copy the Windows 95 setup files to a (second) IDE hard disk.

Phase 4: Format the primary hard disk

The Windows 95 setup is not smart enough to automatically partition and format the primary hard disk (where Windows 95 will be installed). ANY EXISTING DATA WILL BE LOST BY FORMATTING THE DRIVE! PLEASE BACKUP ANY DATA FIRST!!!

  1. So, first use the fdisk utility on the Windows 98 startup disk or MS-DOS startup disk to repartition the hard disk drive. Please ensure that you backup any data on that hard drive to prevent data loss. Any valuable data should always be backed up so there is no excuse for lost data due to user error.
  2. Create a new FAT16 filesystem on the physical drive. Locate the format utility bundled with Windows 95. The MS-DOS startup disk tends to lack the utilities needed to format the disk but Windows 95 setup disk contains the utility. On the CD-ROM, it tends to be bundled in the win95 folder located on the CD-ROM. MS-DOS maps drive D as the CD-ROM in most cases.
cd D:\win95
format c:


  1. "For Microsoft Windows 95, what are the minimum system requirements?". Retrieved 2018-05-13.
  2. "For Microsoft Windows 95, what are the minimum system requirements?". Retrieved 2018-05-13.
  3. theoligopolist (2017-02-25). "Setting up PCem for Windows 95 games". The Oligopolist's Tutorials. Retrieved 2018-05-13.
  4. ""Out of Memory" Error Messages with Large Amounts of RAM Installed". Support. Microsoft.
  5. "Error Message: Insufficient Memory to Initialize Windows". Support. Microsoft.
  6. Chen, Raymond (August 14, 2003). "Windows 95 doesn't boot with more than 1GB of RAM". The Old New Thing. Microsoft.