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.
Edit the Exec=acroread line to be Exec=acroread %f and save the file.
Can't validate signature on PDF [SSL Error]
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,