There are numerous providers who claim they provide the best email encryption and a couple of them are McAfee, ZixCorp, SymantecCloud, but it really depends on your preference on which one you want to use.
I am not too familiar with Hotmail, but from what I can find Hotmail does not offer email encryption. However, with certain programs, such as freenigma, you can add encryption to your emails.
Both a key and a cipher are required. Many are available, and range from quick and easy to use (but have little security), to relatively secure simple relatively simple systems, to those that absolutely cannot be broken.
Files that have a .P7M extension are encrypted MIME email files which use pkcs #7 encryption standards.
Almost every email provider can offer signature encryption. Lotus notes and Outlook are two main email and service providers that offer encryption and protection.
To include a confidential statement in an email, you can add a disclaimer at the end of the email stating that the information is confidential and intended only for the recipient. Additionally, you can mark the email as "confidential" or use encryption to protect the content.
Public Key Encryption
Public Key Encryption
Some messages will require encryption.
128 BIT-ENCRYPTION
To securely make a mobile deposit through email, use a secure email service with encryption. Attach a photo of the check to the email and include any required deposit information in the message. Make sure the email is sent to a trusted recipient, such as your bank's secure email address.
All the protocols that end with S, (SMTPS,POP3S,ESMTPS,POP3S and HTTPS) use Security Socket Layer (SSL) encryption or Transport Layer Security (TLS) encryption to protect the contents of emails.