Retarus Automates User Management with API-Based Provisioning

Secaucus, August 19, 2026 //

Retarus has enhanced the administration API of its Secure Email Gateway with cutting-edge provisioning capabilities. Companies are now able to manage users, personal and alias email addresses, domains, and forwarding rules directly via REST APIs – without having to rely on conventional directory synchronization. Retarus offers a new “directory-free” solution to simplify administration tasks, synchronize changes in real time, and grant IT teams more control in their management of users. Companies stand to benefit from a reduction in manual administrative effort, less susceptibility to errors, and fewer security and compliance risks thanks to faster onboarding and offboarding. Combined with the existing configuration options for day-to-day operations, this functionality is perfectly aligned with Retarus’ holistic API approach – consolidating all email-related interfaces across the entire lifecycle and making them available via a single, central administration API.

Many companies have thus far been managing their email infrastructures using traditional directory synchronization (DirSync), in which user information is transferred as files at regular intervals. In addition to generating a high administrative workload, the approach delays changes until the next synchronization run. By way of the new API-based provisioning, Retarus has now replaced the older procedure with direct, automated intercommunication between the customer’s directory services and the Secure Email Gateway.

Automating and integrating user management seamlessly

Using the new capabilities offered by the API, companies can integrate user and domain management directly into ITSM workflows and automate lifecycle processes across the board. This eliminates the need for directory files to be created and transferred manually. In addition to administrating users, the API also supports the automated management of email addresses, aliases, domains, and forwarding rules. Following the initial synchronization, only changes are transmitted, ensuring that new users are immediately available while deleted accounts or modified permissions are also incorporated in real time. This significantly reduces the manual coordination involved in onboarding new employees, handling position-related changes, or making other adjustments to the organizational structure. The benefits are especially significant for companies with multiple locations or extensive user directories.

From provisioning to operation: Just one central administration API gives you more control

Retarus’ new API-based provisioning also raises the level of operational control within IT teams by giving them full control over their user data. IT administrators can update user data directly whenever required, without being bound to fixed synchronization intervals. Companies can thus decide for themselves when changes should be made, meaning they retain control over their administrative processes at all times. Transaction logs and instant error messages further ensure transparency while facilitating monitoring and troubleshooting. Combined with the existing configuration options offered by the comprehensive administration API, settings such as allow and block lists or company policies can be managed during ongoing operations via a uniform interface using identical API credentials.

To ensure secure connectivity, the solution uses state-of-the-art Oauth2 authentication in conjunction with Retarus Identity & Access Management. Granular role and permission models ensure that read, write, or administrative rights can be assigned specifically to individual service accounts.

Retarus's holistic API approach aims to consolidate all email-related interfaces across their entire lifecycle into a single central administration API and make them centrally available.

Effortless integration into modern cloud environments

The API only needs the rights required to access the cloud directory – for example, via Microsoft Graph – and does not rely on any additional DirSync servers or local synchronization services. This makes the solution particularly easy to implement and just as straightforward to deactivate. Especially companies with Microsoft 365 environments, cloud-based infrastructures, or ongoing migration projects stand to benefit greatly from this streamlined architecture. While new customers can profit from API-based provisioning directly, existing customers have the option of continuing to employ their current DirSync solutions in parallel and migrating to the new technology in stages.

“Nowadays, IT departments expect management processes that can be automated and integrated seamlessly into existing workflows,” says Sören Schulte, email security expert at Retarus. “With our unified APIs, we’re laying the foundation for our customers to benefit from ‘directory-free’ administration backed with maximum control and security – from automated provisioning and configuration during ongoing operations to transparent monitoring capabilities. This effective combination of provisioning, configuration, and observability metrics ensures a consistent, centralized administration API that is unique in the market.”