CodeTwo Email Signatures for Office 365

email signatures for office 365 bullet logo   Centrally managed, server-sided email signatures for Exchange Online
email signatures for office 365 bullet App Source Microsoft AppSource trusted app Gold Award Gold Award
email signatures for office 365 bullet globe World's only email signature solution with:
  Server-sided signatures visible while composing emails,
Office 365 users' photos in signatures &
24-hour support
Free trial
  14-day trial - no credit card required
  See subscription pricing
Log in
  For existing users

Reliability and security

CodeTwo Email Signatures for Office 365 uses cloud services for email processing and adding email signatures and disclaimers. The software requires your Office 365 email flow to be routed through CodeTwo Email Azure Service hosted on ISO 27001 certified Microsoft Azure servers. You can be sure your emails and credentials remain safe and are neither stored on any servers nor read by anyone.

Read on Microsoft's blog how we develop cloud solutions and protect your data. Then take a look below to find out how our email processing infrastructure was designed to meet the high security and reliability standards of business communication.

Email Signatures Office 365 Security

CodeTwo Email signatures for Office 365

Reliability and security

Email Signatures Office 365 ISO Powered
Email Signatures Office 365 OAuth 2.0
Email Signatures Office 365 TLS encryption
Email Signatures Office 365 no external endpoints
Email Signatures Office 365 geolocation
Email Signatures Office 365 private storage
Email Signatures Office 365 emails not read
Email Signatures Office 365 load balancing
Email Signatures Office 365 unnoticable delay
Email Signatures Office 365 99.99% uptime


Powered by ISO 27001 certified Microsoft Azure™

Although the program’s email processing service sits in the cloud, your Office 365 email never leaves Microsoft datacenters. CodeTwo services are located on ISO 27001 certified Microsoft Azure servers, which offer high security and SLA standards. During the setup process, you are asked to choose 1 from 7 available geolocations for the CodeTwo Email Azure Service.

OAuth 2.0 protocol safeguards your credentials

Before setting up any email signature rules, your Office 365 tenant needs to be registered in CodeTwo Email Azure Service. The service itself, however, uses Office 365 OAuth 2 authentication, which doesn’t require our application to collect and store any user credentials at any point. 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. 

TLS encryption and authentication

Every component involved in the email processing pipeline is authenticated with TLS. The 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 flow, you can be sure that messages travel only 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 native Azure and Office 365 features, e.g. the previously mentioned EOP.

Geolocation of your choice (GDPR compliant)

The solution lets you choose from 7 service geolocations to help you stay GDPR complaint. During the tenant registration process, you are asked to choose whether you want your emails to be routed through CodeTwo Email Azure Service located in North Europe, West Europe, North Central US, West US, UK South, Australia East or Canada East (more geolocations coming soon).

Private storage for your settings

CodeTwo Email Signatures for Office 365 does not store your email or credentials but it stores your email rules settings in the Azure™ cloud in one of the 7 different geolocations of your choice (North Europe, West Europe, North Central US, West US, UK South, Australia East and Canada East). 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

Your emails only pass through CodeTwo services to get the signatures.They are neither stored anywhere or read by anyone. The same applies to your Office 365 credentials (see OAuth 2.0 protocol safeguards your credentials).

Efficient load balancing and scalability

Load tests and performance enhancements were one of the key parts of the beta program before the product was launched. The program uses the technology that we've been developing for 10 years and its infrastructure is designed for maximum performance and reliability. The implemented load balancing mechanisms regulate the number of virtual machines responsible for processing emails in every geolocation and can scale in real time depending on the current email traffic in a given location.

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 our extensive tests reached 6 seconds when compared to Office 365 clean setup (with no relay set up). This means your users will hardly be able to see any delays in email delivery time after you set up the connectors, and the operation of the application won’t have any impact on their work efficiency.

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.