Once opened, go to and enable "Enable Protected Mode at startup" for maximum safety against modern PDF exploits.
If your PC runs Windows 7, download SumatraPDF . It’s open-source, actively updated, and opens PDFs much faster than Reader XI ever did.
Adobe Reader XI was highly regarded for its stability and lightweight performance compared to modern cloud-integrated versions. Its core features included: Compare Adobe Reader XI and Adobe Acrobat Reader DC
Click "Accept" after reading the EULA.