Abstract: A method for verifying an email includes storing a first email address and a first address of a first computer system associated with a first email user, and a second email address and a second address of a second computer system associated with a second email user. The method also includes receiving a first email indicating the first email address as an email sender, the first email indicating the second email address as an email recipient. The method further includes retrieving the first address and the second address based on receiving the first email. The method also includes sending an inquiry message requesting confirmation of the first email. The method further includes receiving a response message based on transmitting the inquiry message. The method still further includes sending an email confirmation message in accordance with the response message indicating that the first email is valid.

Abstract: A central computer system verifies the identification information and the financial account information provided by consumers through a network of computer systems. Innovative computerized methods are used for the verification. After the verification, when a computer system on the network conducts a transaction with a consumer, the central computer system sends an alert to the consumer so that the consumer can stop the transaction in real time if the transaction is unauthorized.

Abstract: A computer system for verifying whether two existing sets of confidential electronic data are identical by transforming the two existing sets of confidential electronic data into two new sets of electronic data that are no longer confidential, and then comparing the two new sets of electronic data. As a result, the confidentiality of the two existing sets of electronic data is maintained.

Abstract: A central computer system enables a sender to certify a message, such as an email, and a recipient to verify the validity of the certified message. As a result of the certification, users of messages can avoid ransomware attacks and many other types of fraud caused by fraudulent messages.