Key Takeaways
Summary
18 items · 30–60 minutes
Why Preparation Matters More Than You Think
Upgrading an operating system (OS) is one of the more consequential things you can do to a computer. Done right, it refreshes performance, closes security gaps, and brings new features. Done carelessly, it can leave you without access to critical files, break software you rely on daily, or strand you at a login screen with no clear way forward.
The good news: most upgrade disasters are preventable. They happen not because OS updates are inherently risky, but because users skip the groundwork. If you're unfamiliar with terms like drivers, partitions, or system permissions, the plain-language OS terminology guide is a useful starting point before working through this checklist.
This checklist covers everything worth verifying before you click that install button — organized into logical stages so you can move through it methodically.
External Hard Drive or SSD
Used to store a complete local backup of your system before the upgrade begins.
Cloud Backup Service
Provides an off-site backup copy of critical files as a secondary safety net.
OS Developer's Compatibility Page
The official source for hardware requirements and known compatibility issues for the target OS version.
Peripheral Manufacturer Websites
Used to check for and download updated drivers compatible with the new operating system.
The Pre-Upgrade Checklist
Work through each group below in order. Items marked must are non-negotiable; skipping them meaningfully raises the risk of data loss or a broken system. Should items are strongly recommended for most users. Nice to have items add an extra layer of confidence if time permits.
Back Up Your Data
Check Compatibility
Prepare Your System
Document Your Settings
Timing and Rollback Planning
Never Skip the Backup Step
An OS upgrade modifies core system files and, in some scenarios, can result in data loss if something goes wrong mid-installation. A verified backup is your only reliable safety net. Do not begin any upgrade until you have confirmed that a complete, working backup exists on a separate device or storage location.
After the Upgrade: What to Check First
Once the new OS is running, spend a few minutes confirming everything came through intact. Verify that your most-used applications launch correctly, confirm your files are where you left them, and reconnect any peripherals — printers, external drives, and audio devices occasionally need their drivers reinstalled after a major version jump.
Security settings sometimes reset to defaults during an upgrade. Review your firewall, privacy permissions, and any account two-factor authentication settings. For connected home devices on the same network, this is also a good time to review the practices covered in our guide to keeping home devices secure after setup.
If the upgrade is part of setting up a machine more broadly, the new computer setup walkthrough covers post-configuration steps in detail. And for ongoing habits that keep any computer running smoothly over time, see keeping a home computer running well over time.
Rollback Windows Are Limited
Most operating systems allow you to revert to the previous version for only a short window — often 10 to 30 days — before that option disappears. If you encounter serious compatibility issues after upgrading, act quickly. After that window closes, returning to the previous OS typically requires a full reinstall from a backup or recovery media.