The reason why the novel was restricted but the reader could not open it to read could be due to the following situations: 1. The issue of copyright: The novel may be created by different authors or publishing houses, and each work has copyright. Unauthorized readers could not open the novel to read. 2. The copyright has expired: The copyright of some novels has expired, which means that readers can still open the novel without authorization without the permission of the copyright owner. 3. The novel is encrypted: Some novels may be encrypted to prevent unauthorized readers from accessing them. In this case, the reader could not open the novel to read unless they had the encryption key. 4. The novel is banned: If the website or platform where the novel is located is banned, the reader will not be able to open the novel to read. 5. The novel is damaged or lost: If the reader accidentally deleted the novel or it is damaged for other reasons, they cannot open the novel to read. There could be many reasons why a novel was restricted but readers could not open it to read. The readers could try to find the copyright owner of the novel and open the novel to read after obtaining the authorization.