Sounds like a browser issue. You need to put Gnutella forums on the 'allowed' list of sites to visit and keep cookies for in your browser's security settings. Some warning sites give what's known as false-positives which are incorrect responses because they have not updated their settings/database in several years. I'm not sure how many of these security sites there are but am aware not all are trusty for up-to-date standings on security. It might depend on your search engines as to which security databases they use. To be honest, I have no idea how which ones are set into a browser's referral approach. It may even be related to some 3rd party security browser plug-in your are using & which sites you have it set to utilise. I can assure you, not all will be 100% accurate, choose the known ones only.

For Firefox go to the settings/preferences and Security tab, add www.gnutellaforums.com or/& gnutellaforums.com as an exception.

So what topic did you wish to post about originally anyway before you suffered these problems?