CodeTwo Email Signatures for Office 365

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Reliability and security

CodeTwo Email Signatures for Office 365 is an Azure-based cloud service designed to meet the highest security, availability and compliance standards. It’s the world’s most secure email signature solution (recommended by Microsoft), with a 4-layer security system we’ve been developing for years. It’s the only signature management software developed in compliance with both ISO/IEC 27001 (information security) and ISO/IEC 27018 (personal data protection in the cloud).

Click the icons below to learn how CodeTwo ensures the safety of your business email communication.

Esig 365 Security - mobile infographic

ISO/IEC 27001 & 27018

The Information Security Management System (ISMS) implemented in CodeTwo is certified against ISO/IEC 27001 and ISO/IEC 27018, which proves that we follow the best industry standards and practices related to information protection and personal data security in the cloud. We also develop and improve CodeTwo Email Signatures for Office 365 by drawing heavily on the ISMS. This prompts us to consider all security measures already during the design stage of the software development process, and to make these measures available for you by default. We are regularly audited internally and by external auditors, for compliance with both information security standards. 

Learn more about these standards, how we adhere to them, and how can you benefit from our implementation of ISO-certified ISMS

CodeTwo is GDPR, CCPA & PCI compliant

We are compliant with GDPR, CCPA and PCI, and regularly audited. All of our physical data protection measures combined with strict security policies ensure that personal data processed by CodeTwo is safe at all times.

Learn more on our Security & Compliance page

Powered by Microsoft Azure

CodeTwo services are located on Microsoft Azure servers (in 18 different datacenters), which all meet the highest security and availability (SLA) standards. When registering your Office 365 tenant with CodeTwo Email Signatures for Office 365, you are asked to select one out of nine geolocations for CodeTwo services. This is also where the program’s settings and some of your Azure AD data are stored. To get signatures server-side, your Office 365 email is routed through the CodeTwo Email Azure Service that also sits on Microsoft Azure, which means that emails never leave Microsoft datacenters in the process. If you don’t want your emails routed through our servers, you can use client-side mode that adds signatures directly to Outlook. See how it works

OAuth 2.0 protocol safeguards your credentials

CodeTwo Email Signatures for Office 365 uses the OAuth 2.0 protocol for user authorization. Because of that, our software is not required to collect and store any user credentials at any point and you can be sure that your credentials are never accessed or used by CodeTwo. The access to Office 365 tenant settings is granted according to access tokens issued by Office 365 API and is entirely handled by Office 365 native mechanisms. 

Support for multi-factor authentication

CodeTwo Email Signatures for Office 365 complies with security standards imposed by Microsoft. This also applies to multi-factor authentication (MFA). When enabled in the Office 365 organization, MFA ensures an additional layer of protection when logging into the Office 365 account. And while connecting CodeTwo Email Signatures for Office 365 to the tenant, there is no need to disable multi-factor authentication on your admin account - MFA is supported. 

TLS encryption and authentication

Every component involved in the email processing pipeline is authenticated with Transport Layer Security (TLS). A TLS certificate is generated individually for your tenant upon its registration, ensuring uninterrupted and secure mail flow. Every time a message leaves your Office 365 tenant to be processed by CodeTwo Email Azure Service, it is filtered by Exchange Online Protection (EOP) mechanisms and verified whether it was forwarded by an authorized server. The same procedure is triggered when processed emails are sent back from CodeTwo Email Azure Service to the original tenant. Thanks to this mail processing flow, you can be sure that messages only travel down a secure and verified pipeline and can’t be hijacked by hackers at any point.

No external endpoints

One of the key aspects of our cloud infrastructure is that it can be only accessed from a closed and protected internal network of Azure servers. We don’t open any public endpoints to any external services. We also don’t use any web services or public API calls. Every communication happens ‘behind closed doors’ and can’t be accessed from the outside. This is ensured by CodeTwo programmatic solutions, as well as by native Azure and Office 365 features such as Exchange Online Protection (EOP).

Geolocation of your choice (GDPR and CCPA compliant)

CodeTwo services are available in 18 Azure datacenters spread across 9 geolocations. During the tenant registration process, you can choose a specific geolocation. This helps you stay GDPR and CCPA compliant, as you know exactly where your data is stored and processed. You can decide to keep your signature settings and (if you use server-side or combo mode) have emails routed through CodeTwo Email Azure Service located in West US, North Central US, Canada East, North Europe, UK South, Germany West Central, West Europe, Australia East, or UAE North (more geolocations coming soon).

Encrypted emails supported

Email signatures can be added to protected messages. No matter if you use Office 365 Message Encryption, apply sensitivity labels created in the Azure Information Protection, or digitally sign emails in Outlook (S/MIME), CodeTwo Email Signatures for Office 365 lets you add client-side signatures when composing an email in OWA and Outlook for Windows (and soon also in Outlook for Mac). This means that the signature itself is encrypted together with the message that you send. Office 365 email encrypted server-side will get server-side signatures as long as the encryption takes place after your outgoing messages are routed through the CodeTwo Email Azure Service.

Private storage for your settings

CodeTwo Email Signatures for Office 365 does not store your emails or credentials, but it saves your email rules settings in the Azure cloud, in one of nine different geolocations of your choice. This storage is private and completely unreachable for any external users or software. Thus, you can be sure that your settings are safe and that only you can create, change, or delete them. 

Your emails are not stored or read

Server-side signatures are added when your emails pass through CodeTwo services. Client-side signatures are added directly in Outlook, so no additional routing occurs. No matter what signature type you use, your messages are neither stored anywhere nor read by anyone at CodeTwo. The same applies to your Office 365 credentials (see OAuth 2.0 protocol safeguards your credentials).

Built-in resiliency and scalability: 4-layer security

Our services are designed for maximum performance and reliability and are protected by a proprietary 4-layer security system we’ve been developing for years. The HAC (high-availability cluster) load balancing mechanisms implemented in every geolocation can scale our services in real time up to 25 times depending on email traffic. All instances of the services are continuously health-checked, automatically healed and are paired with secondary load-balanced services that can take over immediately. This is further protected by tertiary services in another geolocation in the same region. And then there’s the final fourth layer - failover services. This modern active-active approach ensures maximum flexibility, resiliency and high availability.

Unnoticeable delay

We wanted to make sure that our services never add more than a few seconds of delay to the email processing time and we reached our goal. The average overhead we observed in server-side mode during our extensive tests reached 6 seconds when compared to Office 365 clean setup (with no email relay set up). This means your users will hardly be able to see any delays in email delivery time after you set up our connectors, and the functioning of the application won’t have any impact on their work efficiency. And if you ever need to change any aspect of your signature rule or update a signature template, these changes go live instantly after you save them in CodeTwo Email Signatures for Office 365.

99.99% uptime

Since going live, CodeTwo Email Signatures for Office 365 has consistently maintained a high average uptime of 99.99%. This means that our service matches the highest standards of uptime guaranteed by Microsoft's Cloud services. Moreover, our email signature service is fault tolerant, which means that if it went down, its failover capability would automatically reroute your emails through secondary servers in your geolocation and safely deliver them to final recipients (learn more). On top of that, CodeTwo engineers monitor the program’s behavior and performance 24 hours a day, 7 days a week, to ensure CodeTwo Email Signatures for Office 365 is always kept in peak operating condition. You can view the current state of CodeTwo services in all geolocations at a dedicated status page.

Role-based access control (RBAC)

CodeTwo Email Signatures for Office 365 lets the administrator assign different types of permissions to the service. Thanks to that, you can let one of your teams (e.g. Marketing) design email signatures for the whole company. Another team could be allowed to manage tenants and subscriptions only. At the same time, you do not have to assign any additional permissions in Office 365, reducing the risk that any team member will make use of elevated privileges to perform any administrative tasks.

Mailbox backup solution

CodeTwo Email Signatures for Office 365, apart from unifying your Office 365 email signatures, lets you claim a free yearly subscription of CodeTwo Backup for Office 365. This professional backup software will let you secure your Office 365 data and restore it whenever you want. Learn more...