Bill from the UK writes: "I'm 66 and not a tech guy. I've just been kicked back as a "KNOWN SOURCE OF SPAM (NJABL)" although I don't generate spam. I do occasionally send large files to business associates, and some get kicked back because of size, but that's all. How can I become 'unlisted' or at least get in touch with the generators of this incorrect information. Thank you very much."
NJABL ("Not Just Another Bogus List") is a DNSBL ("DNS-based blacklist"). If you don't know what that is, don't worry -- it's basically just a kind of spam filter. It's used by mail server administrators to try to block incoming spam. According to NJABL's website, their listing critiera includes "known and potential spam sources (open relays, open proxies, open form to mail HTTP gateways, dynamic IP pools, and direct spammers) for the purpose of being able to tag or refuse email and prevent at least some spam."
Bill, here's the deal. You're trapped in a situation where NJABL has chosen to list your ISP (Tiscali). If they're mad at anybody, they're mad at Tiscali, and not at you. Ultimately, what you need to do is contact Tiscali, tell them that because of this, you are being incorrectly labeled as a spammer, and you need them to address this issue with NJABL.
If you contact NJABL directly, they are going to likely just tell you the same thing. It's all about who owns the mail servers, not individual users on the mail server. So, there is a spam issue (or perceived issue) with Tiscali -- not with you. You're finding out that end users often get stuck in the middle when these types of issues occur. One point of view here is that it's Tiscali's fault, for perhaps allowing enough spam to come from their network that their users' mail is getting blocked. An alternate viewpoint holds that it's NJABL's fault, for being too agressive in their blocking policies, allowing non-spamming end users like yourself to be negatively affected.
Regardless of who is to blame, it's not an issue that you're going to have success fixing on your own. Contact Tiscali, detail the issue for them, and request that they contact NJABL to resolve this problem. When you reach out to your ISP, be sure to include the entire error message. There is information about the issue contained in this error message that both Tiscali and NJABL will need to figure it out.