Overview

Legacy software may not run on modern operating systems. This guide shows you how to run old programs using compatibility modes, virtual machines, or find suitable modern replacements.

Step 1: Windows Compatibility Mode

1

Run Program in Compatibility Mode

Right-click program's .exe file or shortcut
Select Properties
Click Compatibility tab
Check "Run this program in compatibility mode for:"
Select older Windows version (e.g., Windows 7, Windows XP)
Click Apply, then OK
Launch program to test

2

Use Compatibility Troubleshooter (Automatic)

Right-click program → Properties → Compatibility tab
Click "Run compatibility troubleshooter"
Select "Try recommended settings"
Click "Test the program" to try settings
If works, click "Yes, save these settings"
If doesn't work, try "Troubleshoot program" for manual options

Pro Tip:

Start with Windows 7 compatibility. If that fails, try Windows XP (SP3) for very old software.

3

Additional Compatibility Settings

Reduced colour mode: For old games needing 16-bit colour
Run in 640×480 resolution: For software designed for old monitors
Run as administrator: For programs needing elevated permissions
Disable fullscreen optimisations: For games with display issues
Test combinations of settings until program works

4

Program Compatibility Assistant

Windows detects incompatible programs automatically
Popup appears after program closes or fails
Click "Run the program using recommended settings"
Windows applies best guess at compatibility settings
Save settings if program runs successfully

Security Warning:

Running programs as administrator and in compatibility mode can reduce security. Only use for trusted software.

Step 2: Mac Compatibility Solutions

1

Rosetta 2 (Intel Apps on Apple Silicon)

M1/M2/M3 Macs can run Intel-only apps via Rosetta 2
First time opening Intel app, Mac prompts to install Rosetta
Click "Install" and enter password
One-time installation, works for all Intel apps
Apps run slightly slower but usually unnoticeable

2

Manually Install Rosetta 2

Open Terminal (Applications → Utilities → Terminal)
Type: softwareupdate --install-rosetta
Press Enter, then A to agree to licence
Installation takes 1-2 minutes
No restart needed

3

32-bit Apps on macOS (No Longer Supported)

macOS Catalina (2019) and newer don't support 32-bit apps
Check if app is 32-bit: Apple menu → About This Mac → System Report → Applications
Options: Contact developer for 64-bit update, find alternative app, or use virtual machine with older macOS

Important:

32-bit Mac apps will never run on macOS Catalina or newer. Developer must release 64-bit version or app is obsolete.

4

Windows Programs on Mac

Use Parallels Desktop (paid) or VirtualBox (free) to run Windows
Install Windows 10/11 in virtual machine
Install Windows programs inside virtual Windows
Requires Intel Mac or Parallels with Windows 11 ARM on Apple Silicon

Step 3: Virtual Machines for Legacy Software

1

When to Use Virtual Machines

Software absolutely won't run in compatibility mode
Need complete old operating system (Windows XP, Windows 7)
Running Windows software on Mac or Linux
Testing software in isolated environment
Business software requiring specific OS version

2

VirtualBox (Free, Beginner-Friendly)

Download from virtualbox.org
Install VirtualBox on host computer
Obtain Windows installation media (ISO file)
Create New Virtual Machine in VirtualBox
Allocate RAM (4GB minimum) and disk space (50GB recommended)
Install Windows in virtual machine
Install legacy software inside virtual Windows

3

VMware Workstation (Professional Option)

Better performance than VirtualBox
Easier file sharing between host and guest
Paid software (£200+) but free trial available
Supports newer features like 3D graphics

4

Windows 10/11 Built-in Hyper-V (Pro/Enterprise Only)

Windows → Turn Windows features on or off
Enable Hyper-V (requires Windows Pro or Enterprise)
Restart computer
Open Hyper-V Manager from Start menu
Create virtual machine for legacy Windows version

Performance Tip:

Virtual machines run best with at least 8GB RAM on host computer. Allocate half to virtual machine.

5

Licensing Considerations

Windows in virtual machine requires separate licence
Windows 7/8/10 can be purchased from Microsoft
Or use existing licence key if you have one
Linux virtual machines are free and don't need licence

Step 4: Modern Alternatives to Legacy Software

1

Office Software Alternatives

Old Microsoft Office: Use Microsoft 365 (subscription), LibreOffice (free), or Google Workspace
WordPerfect: LibreOffice Writer can open old WordPerfect files
Lotus 1-2-3: Excel or Google Sheets with file conversion

2

Design & Creative Software

Old Adobe CS versions: Upgrade to Creative Cloud or use Affinity suite (one-time purchase)
CorelDRAW: Use latest version or switch to Adobe Illustrator
Paint Shop Pro: GIMP (free) or Photoshop Elements

3

Accounting & Business Software

QuickBooks (old versions): Upgrade to QuickBooks Online or switch to Xero
Sage (legacy): Upgrade to Sage 50cloud or Sage Business Cloud
Custom database apps: Consider rebuilding in modern platform or cloud service

Business Critical Software:

Consult IT professional before migrating business-critical software. Data migration and training should be planned carefully.

4

Games

Old PC games: GOG.com sells updated versions compatible with modern Windows
DOSBox: Free emulator for very old DOS games
Steam: Many classic games updated for modern systems

5

When to Migrate vs. Maintain Legacy

Migrate to modern software if:

Security updates no longer available
Software can't run on modern hardware
Files can't be shared with others
Modern alternatives offer better features

Keep legacy software if:

Business-critical with no suitable replacement
Custom-built for specific workflow
Migration costs exceed maintaining virtual machine
Works perfectly in compatibility mode or VM