The Microsoft Edge browser is the default app for PDF files on Windows PCs. However, you can easily change your default PDF viewer to Adobe’s Acrobat Reader DC for files saved to your Windows PC.

Click on the Download option at the top, and OneDrive will now download all files to the PC at once. It worked just fine for me on my Windows 11 PC and here is the screenshot.

No matter your operating system, knowing how to combine PDF files is a good skill. We'll teach you the best ways to do so for Windows, macOS, or via the web.