Browsing Dutch translation

48.

**Virus checking**: If you want all files uploaded by users to be run through a ClamAV virus scan, you should select the virus checking option. You have to have `ClamAV <http://www.clamav.net/>`_ installed on your server.

49.

**Path to clam**: The filesystem path to clamscan or clamdscan for virus checking. It is assumed that a failure of ClamAV to run will mean that a file should be treated as a virus, and a quarantine directory will be automatically set up by your Mahara installation.

50.

**Anti-spam**: There are three levels of anti-spam protection available for publicly visible forms, such as the contact and registration forms. A form submission is never silently rejected. Rather, an error message is displayed asking the user to try again if the submission is classified as spam. The three choices are:

51.

**None**: No anti-spam checks are performed on form submissions.

52.

**Simple**: Some basic checks are performed. Form submissions with email addresses that are not well-formed or that have an excessive number of URLs are rejected.

53.

**Advanced**: Performs additional checks to determine whether email addresses are real or contain URLs that are blacklisted. This requires an internet connection.

54.

**Enable Spamhaus URL blacklist**: If enabled, URLs will be checked against the Spamhaus DNSBL. The `Spamhaus Project <http://www.spamhaus.org>`_ provides a URL blacklist that is free for non-commercial, low-traffic use. A professional use datafeed service is also available but not supported in Mahara. Please read the `Spamhaus DNSBL usage terms <http://www.spamhaus.org/organization/dnsblusage.html>`_ before enabling this option.

55.

**Enable SURBL URL blacklist**: If enabled, URLs will be checked against the SURBL DNSBL. `SURBL <http://www.surbl.org>`_ provides a URL blacklist that is free for organizations with fewer than 1000 users. A professional use datafeed service is also available, but not supported in Mahara. Please read the `SURBL usage terms <http://www.surbl.org/usage-policy.html>`_ before enabling this option.

56.

**Disable external resources in user HTML**: Turning this option on will prevent users from embedding external resources such as images from remote sites into their forum posts and other HTML content. It is however a good thing to do from a security standpoint since it does neutralise a few clever phishing attacks. See the `HTML Purifier documentation <http://htmlpurifier.org/live/configdoc/plain.html#URI.DisableExternalResources>`_ for more details.

57.

Proxy settings