Cyber conmen are cashing in on interest surrounding the Pottermore website.
Through Pottermore, JK Rowling will release more stories and background from the world of Harry Potter.
Pottermore officially opens in October, and scammers are selling fake accounts for the site that claim to give fans early access.
They are also using search engine poisoning to direct Potter fans to sites that are seeded with viruses and other malicious programs.
Discovered by veteran security researcher Chris Boyd, the scams largely revolve around early access to the Pottermore website.
The public at large will be able to sign up in October but early, or beta, access is being granted to people before then if they are among the fastest to complete a magical quill challenge on the Pottermore site.
The challenge runs every day from 31 July to 6 August and about one million beta accounts will be given away.
Scammers are now offering to register people for this challenge and are getting hold of their personal details as a result. Also, Mr Boyd discovered, some scammers are supposedly selling Pottermore accounts for about $100 (£60) via eBay.
While many of these are likely to be fake, some are being offered by fans who have set up more than one account for Pottermore.
The administrators of the Pottermore website have noticed the trade in accounts and have issued a warning about the practice.
In a blog post, the Pottermore administrators said buying and selling accounts was "expressly prohibited" in the terms and conditions. Also, it added, signing up with a view to selling an account "deprives genuine fans the chance to gain early access".
It added: "We have the right to terminate any Pottermore accounts that are sold online."
Videos of people successfully signing up to Pottermore are being posted on YouTube but, found Mr Boyd, many lead to surveys tied to affiliate marketing schemes. Those who fill in the surveys get the offer of a download as a reward that is often found to be full of malware or adware.
Scammers are also starting to poison search engine results associated with Pottermore to direct people to sites loaded with malicious programs.
One site found by Mr Boyd is known to have harboured fake security software that claims to find viruses on a PC and asks for cash to clean up the non-existent problem.