Can guest users post to your forum? Why not? If you are a small forum, you lose a lot of postings. Users are lazy, they don't like registering. Instead, they go to a more friendly forum.
Allow guest posts, and your forum will be more popular. Unfortunately, also between spammers.
The magic bubble of Links Rejector is filtering contact information. If an unregistered user posts a link, the whole posting is rejected. All the spam has links, therefore all the spam is rejected.
Posting is rejected by Links Rejector
Note that Textual Confirmation and Links Rejector benefit the community by sending updates to the spam database. If you don't like it, then these tools are payware for you.
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