Back up your Windows files before you switch

Copy your files to an external drive before you install Linux. Yes, even if Windows is staying.

Mint’s installer has an option called Erase disk and install Linux Mint, and it does what the label says. The option you meant to choose is right beside it. Installing an operating system is the one afternoon of the year when a single misread screen can empty a disk, so make the copy first and the worst outcome shrinks to a wasted evening.

What to copy

Open File Explorer and click your name under This PC, or go to C:, then Users, then your name. Nearly everything that’s yours lives in that one folder, so copy Desktop, Documents, Downloads, Pictures, Music and Videos out of it and onto the external drive.

Then go looking for strays. Some programs keep their work in a folder of their own directly on C:, outside your user folder, where a tidy copy of Documents will miss it. If a program matters to you, open it, find its Save As or Export screen, and note where it’s been putting things.

Ignore the programs themselves. Windows apps can’t be copied across and wouldn’t run if they were. You’re saving what you made, and each app’s page tells you what will open it afterwards.

The OneDrive trap

If File Explorer shows a little cloud icon beside a file, that file isn’t on your PC. Microsoft’s Files On-Demand feature shows everything in your OneDrive as though it were local and only downloads a file when you open it.

This cuts both ways. Copying a cloud-only folder to an external drive can trigger a very long download. But those files are also the safest ones you own, because they live on Microsoft’s servers and OneDrive works in a browser on Linux. You can leave them where they are and sign in from the other side.

The files to worry about are the ones with no cloud icon, because those exist only on this PC and nobody else holds a copy.

Browser bookmarks and passwords

If you sign in to Chrome, Edge or Firefox with an account and sync is on, your bookmarks and saved passwords will reappear when you sign in to the same browser on Linux. All three have Linux versions.

If you don’t sync, export the bookmarks. Chrome’s help pages describe it: the bookmark manager has an Export Bookmarks option that saves everything as a single HTML file, which any browser can import. Put that file on the external drive with everything else.

Two things that aren’t files

Your BitLocker recovery key, if your laptop’s disk is encrypted. The hardware guide explains why, and Microsoft’s page shows where to find it. Write the 48 digits on paper.

Licence keys for software you paid for and might reinstall on another Windows PC one day. They’re usually in the email receipt.

Check the copy

Unplug the external drive, plug it back in, and open a few things from it. A photo, a spreadsheet, the oldest document you care about.

Better still, take the drive along to your USB test drive and open the same files from the Linux desktop. Two questions settled at once.

Then put the drive in a drawer and leave it alone until the install is finished.