Troubleshooting & help
Adobe updates Reader regularly to safeguard your system against malicious attacks through PDF files. If you receive multiple update messages, make sure that the last update is fully installed. Double-click the Reader installer that you downloaded to complete the installation. For information on switching to automatic updates, see Automatic updates | Acrobat, Reader.
Many web browsers, such as Chrome, Firefox, and Safari, now use their own PDF viewer instead of the Adobe PDF plug-in. For best results, configure your browser to use the Adobe PDF plug-in to open online PDF files. To solve the most common PDF-display issues, follow the steps in Troubleshoot viewing PDF files on the web.