Pre-requisites: Have ClamAV installed and configured on the system, to use in testing: FIrst, install clamav: sudo apt-get install clamav clamav-daemon Then, enable clamav via admin > plugins > antivirus plugins > manage antivirus plugins Then click settings for the clamav scanner and enter "/usr/bin/clamscan" in the pathtoclam field adn save. Test an unmodified virus scanner 1) Visit https://www.eicar.org/?page_id=3950 and download the eicar test file. 2) Visit /user/files.php and attempt the upload the eicar file. 3) Verify that a message box appears with the message: 'eicar.com has been scanned by a virus checker and found to be infected!'. This confirms the default message is being displayed by scanners that do not implement the optional method, such as ClamAV   Test a virus scanner that implements a custom message 4) Install an encrypted content scanner for use in testing: git clone git @github .com:catalyst/moodle-antivirus_encrypted.git lib/antivirus/encrypted 5) Visit /admin/index.php to perform the upgrade 6) Visit /admin/settings.php?section=manageantiviruses and enable the encrypted content scanner. 7) Download the attached doc file. It is a password protected libreoffice doc with the password 'password'. 8) Go back to /user/files.php and attempt to upload the encrypted doc. 9) Verify you receive a custom error message specific to this scanner: 'Test doc enc.odt was unable to be inspected, due to encryption on the file.'