To set the default program for opening PDF files, you can use either of these methods:
Method 1 – From a PDF file
1. Right‑click any PDF file.
2. Choose Open with… → Choose another app.
3. Select the program you want (e.g., Adobe Acrobat Reader, Edge, Chrome, etc.).
4. Check Always use this app to open .pdf files and click OK.
Method 2 – From Windows Settings
1. Open Control Panel → Default Programs.
2. Click Set your default programs.
3. In the list, find the program you want to use for PDFs and select it.
4. Click Set this program as default (or use Choose defaults for this program and ensure PDF is checked).
Either method will make the chosen application the default viewer for all PDF files.