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OASIS MailGuard - Secure Encrypted Email Service

Encrypted email your team and clients will love to use

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The basics How it works

What is Email Encryption Software? Email encryption software protects the contents of an email by converting it into a secure, unreadable format that can only be accessed by the intended recipient. It safeguards sensitive information in transit and at rest, helping organisations maintain confidentiality, meet compliance requirements, and reduce the risk of data breaches.

Most secure informationsharing tools forget one vital thing – the human factor. No matter how secure your system, if employees and clients avoid using it because it’s slow or complex, it won’t protect you from risk. Secure Messaging is the easiest way to encrypt and send confidential or sensitive data. You can send information protected with military-grade AES-256 encryption from within your standard Microsoft Outlook window. What’s more, when your clients reply, their messages and attachments will be protected to the same level, free of charge to them. We’ve stripped out the time-consuming steps which cause frustration in traditional secure email, portal, or mobile app messaging. Not only that – we’ve added in extra protections. Our emails are encrypted both in transit and at rest. You can even send messages securely to a shared inbox, by including a question or SMS code known only to the intended recipient. And by switching from registered post to a secure digital system, you’ll save on costs and carbon emissions.

Write and respond to emails securely from within Microsoft Outlook

Remove frustrating, time-consuming steps and achieve 80% email open rates

Offer clients a free, secure way to send you their confidential information

Comply with ISO guidelines with end-to-end military-grade AES-256 encryption

Lower costs and carbon emissions by switching from registered post to Secure Messaging

The OASIS difference Why choose Secure Messaging from OASIS?

Secure – in transit and at rest

Other ‘secure’ email services only protect information in transit – Secure Messaging protects it at rest too, in line with Information Commissioner’s Office (ICO) guidelines. 

Manual or automated encryption

Rules can also be configured within your mail server to automatically encrypt sensitive messages or prompt the sender to encrypt manually before sending. 

Happier team, happier clients

It’s quick and simple for employees to send information securely, directly from their Outlook window. And all recipients get a free account to reply with the same level of protection. 

Trusted by leading organisations

11,500 customers across Europe trust our services, which are certified to the highest standards including ISO 27001, ISO 22301:2019 and Cyber Essentials Plus. 

Secure batch sending

If you regularly send large volumes of batched messages (like account statements), our bulk sending feature lets you work both quickly and securely. 

One partner, zero stress

Outsource your end-to-end records management to Europe’s largest privately owned information management supplier, from storage to scanning to secure messaging. 

Can OASIS MailGuard be integrated with our current email systems?

Yes. OASIS MailGuard integrates seamlessly with Microsoft Outlook, so your team can write and reply to secure emails right from their existing Outlook interface without needing new apps or portals

Does OASIS MailGuard support secure messaging for compliance requirements?

Absolutely. MailGuard delivers military-grade AES-256 encryption for emails both in transit and at rest, in line with Information Commissioner’s Office (ICO) guidelines. That dual protection helps satisfy stringent compliance needs for data handling and confidentiality

How does OASIS MailGuard compare with other encrypted email providers?

MailGuard strips out the typical friction of secure communication no clunky portals or complex steps. It’s built to be user-friendly: send encrypted messages from Outlook, empower clients to reply securely (for free), and benefit from features like batch sending and automated encryption rules. Other solutions often require separate logins or lack encryption at rest MailGuard avoids those pitfalls

What types of organisations benefit from OASIS MailGuard?

Any organisation that needs to manage confidential communication securely and efficiently will benefit. This includes legal, healthcare, finance, public services, and any business moving from registered post to digital messaging. And with OASIS trusted by 11,500 customers across Europe including highly regulated sectors, MailGuard is fit for enterprises of all sizes

What encryption standards and certifications does OASIS MailGuard hold?

MailGuard uses end-to-end AES-256 encryption the same military-grade standard trusted globally. It’s supported by the same rigorous certifications that underpin all OASIS services, including ISO 27001, ISO 22301:2019, and Cyber Essentials Plus

How does OASIS MailGuard help reduce organisational risk and carbon footprint?

By replacing traditional, slower methods like registered post with secure digital messaging, MailGuard reduces costs, process delays, and carbon emissions. This approach aligns with OASIS’s broader investments in sustainable operations and reduction of digital waste helping your organisation lower both environmental impact and exposure to communication risk

Digital technologies Bringing records management up to date, from mailroom to boardroom

Wherever you want to introduce digital processes to improve your operations, we’ve got the agility, the experience and the technology to help.

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