PDF

Please note that Adobe no longer supports Acrobat Reader for Linux. The latest native Linux version is 9.5.5 dated from 26/04/2013. From this reason you should refrain using/installing Adobe Acrobat Reader to avoid potential vulnerabilities and hacker exploits.

Installation of Adobe Reader in Ubuntu

sudo wget -O ~/adobe.deb ftp://ftp.adobe.com/pub/adobe/reader/unix/9.x/9.5.5/enu/AdbeRdr9.5.5-1_i386linux_enu.deb

sudo dpkg --add-architecture i386

sudo apt update

sudo apt install libxml2:i386 libcanberra-gtk-module:i386 gtk2-engines-murrine:i386 libatk-adaptor:i386

sudo dpkg -i ~/adobe.deb

Launch Adobe Acrobat Reader on Ubuntu

How to Remove Adobe Reader in Ubuntu

sudo apt-get purge adobereader-enu

sudo apt-get autoremove

How to Set Adobe Reader as default PDF reader

Ubuntu 32 bit

sudo gedit /usr/share/applications/AdobeReader.desktop

Edit the Exec=acroread line to be Exec=acroread %f and save the file.

Ubuntu 64 bit

sudo gedit /usr/share/applications/AdobeReader.desktop

Edit the Exec=acroread line to be Exec=acroread %f and save the file.

Can't validate signature on PDF [SSL Error]

• In Acrobat or Reader, click Edit > Preferences.

• From the Preferences dialog box, select Security on the left.

• Click Advanced Preferences, and then click the Verification tab.

• Select Verify Signature using 'The Current time'

Restart the Adobe reader and validate the signature

Display of Valid Signature in previous version of Digital Signature:

Display of Valid Signature in Current Version of Digital Signature:

Digital Signature Validation:

After opening the pdf file, click on Signature Panel located at upper right corner of adobe reader. A window will open on left side of document, where all information regarding signature validation is displayed along with the signature details. In case of Valid signature, Green Check will be shown at upper left corner of adobe reader and also inside signature panel itself

In case of Invalid Signature, Red Cross sign is displayed at upper left corner of adobe reader and inside signature panel itself,