I talk about the things that keep Microsoft 365 environments running, and about the people who keep them running. My technical sessions go deep into Exchange, hybrid identities and Microsoft 365. My non-technical sessions cover what happens when the person behind the admin console isn’t OK.
About me
I am a principal technology consultant and the owner of Granikos GmbH & Co. KG in Berlin. I have been a Microsoft MVP for Microsoft 365 and Exchange since 2018 and hold the Microsoft Certified Solutions Master Messaging certification.
I run the community site Exchange for IT Pros and host the podcasts Exchange Unplugged and Cloudchroniken. I have written several books on Exchange Server and Microsoft 365, and I speak in German and English at community conferences and user groups across Europe.
Keynotes
My keynotes connect technology with the human side of IT. They are designed to open a conference day or to close it with a thought people take home.
Stop Winning, Start Being Human – Finding Our Way Back to Each Other
We chase targets, promotions and KPIs, and too often we try to outshine the people next to us. Behind a polite surface, many of us are quietly looking for each other’s weaknesses. This keynote asks what we lose on the path of endless performance, and why that path does not lead to a future we can share. It is not a talk against ambition. It is an invitation to come back to ourselves and to rediscover empathy, respect and genuine collaboration. Because a team is not a leaderboard.
30 to 45 minutes | English or German
The Mask Costs Energy – Honesty, Health and Strength in IT
Every IT team has someone who is fighting a battle nobody sees. This keynote is about invisible illnesses, the energy it takes to keep a professional façade, and the small decisions that turn a workplace into a safe space. It draws on my own experience and on what I see in many customer environments: stories, honesty and concrete ideas for leaders and colleagues.
30 to 45 minutes | English or German
The Voyager Principle – Doing More with What We Have
In 1977, every kilobyte counted. Voyager 1 is still sending data from interstellar space, running on code written with care for every resource. Today, we build AI agents and generate videos as if memory, computing power and energy were endless, and answer the demand with one new data centre after another. This keynote asks what we lost along the way and why efficiency is not nostalgia, but responsibility. A thought for everyone who writes prompts, builds solutions or decides about IT.
30 to 45 minutes | English or German
Letting Go of the Last Server – What Legacy Teaches Us About Change
Every organisation has its “last server”: a system, a process or a habit nobody dares to switch off. Using Exchange as an example, this keynote looks at why letting go is hard, why admitting a past mistake is a strength, and how teams move forward without breaking what still works.
30 to 45 minutes | English or German
Technical Sessions
The Last Exchange Server – Exit or Permanent Guest?
The last Exchange Server in hybrid organisations was never a mailbox problem. It is a source-of-authority problem. This session explains the supported and unsupported ways to get rid of it: Exchange Management Tools, cloud-managed Exchange attributes, writeback with Entra Cloud Sync, and the full uninstall. You will also learn why the Exchange schema stays forever, and why SMTP relay is the most overlooked blocker.
Level 300 | 45 minutes | German, English on request
Delivered at: CDC Germany 2026
The Never-Ending Story of Microsoft 365 Groups
Outlook Group, Unified Group, Microsoft 365 Group: the names change, the confusion stays. No matter where a group is created, its technical home is Exchange Online. This session looks under the hood: architecture, lifecycle and the defaults that cause undeliverable messages and strange routing, especially in hybrid environments. You leave with a practical admin checklist and a provisioning approach that keeps groups consistent.
Level 300 | 45 minutes | English or German
Delivered at: CDC Germany 2026
Also available as a co-presented session with Anja Schröder, adding the SharePoint and Teams perspective.
The End Is Near – Exchange Web Services in Exchange Online
Exchange Web Services in Exchange Online will be switched off on April 1, 2027. This session shows how to find the applications, scripts and hybrid features that still depend on EWS, what Microsoft Graph can and cannot replace, and how to prepare your Exchange Servers for rich coexistence after the switch-off.
Level 300 to 400 | 45 minutes | German, English on request
New for 2027
How Much Energy Does Your Prompt Need? Efficient AI Instead of Endless Data Centres
Voyager 1 crossed the solar system with a few kilobytes of memory. Today, we prompt as if computing power and energy were unlimited. This is not a rant against AI. It is a technical look at what drives resource consumption: tokens, context windows, reasoning models and agents that burn capacity through loops, oversized models and constantly firing triggers, especially low-code agents built by business users. You leave with criteria for model selection, patterns for resource-aware agent design and governance levers for admins.
Level 300 | 45 minutes | German, English on request
New for 2027
Understanding Secure Hybrid Mail Flow
Hybrid mail flow between Exchange Server and Exchange Online is always called “secure”. But what does that actually mean? And how does it work without a dedicated receive connector on-premises? We look at the connector configuration on both sides, certificates and TLS, and the details that decide whether a message is treated as internal or external.
Level 300 | 45 minutes | English or German
Keeping Your Exchange Server Pasture Secure
Exchange Servers are a valuable target for attackers, and installing updates is only the first layer of protection. This session walks through all the layers you need to secure an Exchange Server environment. Afterwards, you can check which measures are already active in your own organization. Sharing experiences with the audience is part of the session.
Level 300 | 45 to 60 minutes | English or German
Modern Exchange Online – Architecture, Security and Operational Practice
A practical look at Exchange Online as a strategic messaging platform: modern authentication, secure message transport, Defender integration, compliance controls and real-world governance. With best practices you can apply in your own tenant right away.
Level 200 to 300 | 45 minutes | English or German
Email Mysteries of Microsoft 365 B2B Guest Accounts
A partner changes its email domain, and suddenly messages to guest accounts in your tenant bounce, even with the correct new address. This session explains the by-design behavior of Entra ID behind it and shows how to fix it in your tenant.
Level 300 | 20 to 30 minutes | English
Non-Technical Sessions
Hidden Disabilities: Courage, Awareness and the Challenge of Speaking Up in IT
IT culture celebrates resilience. Always on, always performing, always available. In 2024, I was diagnosed with an incurable lymphoma, and I had to choose: hide it until I couldn’t, or speak openly. I chose openness. This session explores why IT professionals, especially men, rarely talk about health challenges, the bias that equates illness with unreliability, and the cost of masking while solving everyone else’s problems. You leave with practical guidance for individuals, teams and leaders.
Because strength and vulnerability aren’t opposites. They’re allies.
Lightning Talk 20 minutes or Breakout 45 minutes | English or German
Delivered at: Scottish Summit 2026
Navigating AI in the Workplace – Fears, Feelings and Ways Forward
New Copilot offerings arrive faster than anyone can evaluate them. For many admins and users, this creates a feeling of powerlessness or even fear, and it does not stay at work. This interactive discussion makes room for those feelings and looks at practical ways to deal with change without losing yourself in it.
Panel or interactive session | 45 minutes | English or German
Where I’ve spoken
- 2026: Exchange Summit, Experts Live Germany, MVP Community Week Münster, CDC Germany, Scottish Summit
- 2025: Exchange Summit, Experts Live Germany, MVP Community Week Münster, South Coast Summit, SmartCloud 365, Exchange User Group DACH
- 2024: M365 Community Days at Sea, Exchange Summit, Microsoft 365 für Admins, Scottish Summit
- Earlier: Scottish Summit, Experts Live Austria, European MCT Summit, MEC 2022, Teams Nation, Teams Community Day, aMS Berlin, SharePoint Saturday Cologne, M365 Virtual Marathon and more
Past Sessions
- Exchange Hybrid: What, Why, and How
- Securing Microsoft 365 Data with Service Encryption
- Exchange Server SE: What Happens On-Premises?
- Transitioning from EWS to Microsoft Graph
- Exchange in 2026: Finding the Balance Between On-Premises and Cloud
Slides and Recordings
Invite me
You are organizing a conference, a user group meetup or an internal event? I am happy to adapt sessions to your audience, length and language.
Email: thomas@stensitzki.eu
- Session submissions: Sessionize
- All my channels: Linktree
Speaker bio for your program
Thomas Stensitzki is a principal technology consultant and the owner of Granikos GmbH & Co. KG in Berlin. He has been a Microsoft MVP for Microsoft 365 and Exchange since 2018 and holds the Microsoft Certified Solutions Master Messaging certification. He runs the community site Exchange for IT Pros, hosts the podcast Exchange Unplugged and has written several books on Exchange Server and Microsoft 365.