Microsoft 365 · Azure · Modern Workplace
Welcome to the Röstmeister.
I'm Ferdi Lethen-Oellers, Microsoft MVP and Senior Consultant at amexus. On this site I share what I've learned in Microsoft 365 and Azure projects and explain it so that decision makers, project leads and admins know exactly what to do next.
- Since 2023Microsoft MVP
- 15 yearsModern Workplace
- Authorat Wiley
- Sessionsacross Europe
Latest from the roastery.
Azure Functions Flex Consumption: VNet, Bicep and the end of Consumption
Flex Consumption brings VNet integration into the serverless model, and the Linux Consumption plan is being retired. What changes and how to set it up with Bicep.
8 min read R-03 · Foundry & AzureMicrosoft Foundry: building agents until they are production-ready
With Microsoft Foundry you build an AI agent in one afternoon. It only becomes secure and maintainable with roles, Entra ID access, guardrails and monitoring.
8 min read R-01 · SharePoint & TeamsCopilot and oversharing: clean up SharePoint before you roll out
Copilot creates no new risk, it makes oversharing visible. How to clean up broad shares in SharePoint before you assign the first Copilot license.
9 min read R-02 · Copilot & AdoptionCopilot Managed Runtime: Governance for Vibe-Coded Apps
Since 25 September anyone who can open Copilot Studio builds apps without code. What the Copilot Managed Runtime changes, where governance stays open, what to do.
9 min readEvery origin
tastes different.
SharePoint & Teams
Information architecture, hub sites, permissions, Viva.
Copilot & Adoption
Licensing, business case, usage data, expectations.
Foundry & Azure
Agents, Bicep, Functions, cost control.
Entra & Security
Conditional Access, Purview, retention, compliance.
Change & People
ADKAR, CLARC, key users, internal communication.
Roastmaster means both.
The master is the one who learned the craft. The roaster is the one who knows when to take the beans out. Both are the same work: heat, time and judgement.
I am a Senior Modern Workplace Consultant at amexus and a Microsoft MVP. I build SharePoint, Teams, Entra and Azure landscapes, speak about them in German and English, and write down what goes wrong along the way.
What fifteen years taught me: the tenant is rarely the problem. The translation is.
Where I'm on stage next.
24 Nov 2026
Fully in control: the new Microsoft Planner as your command centre
SmartCloud
New dates will follow — enquiries welcome via the talks page.
Microsoft 365 administration, in print.
Microsoft 365 Administration für Dummies
624 pages for everyone who runs a Microsoft 365 tenant and wants to know which settings really matter. Published in German.
What's inside
- Wichtige Konfigurationen in der Benutzerverwaltung
- Das Admin Center verstehen und Zusammenarbeit über Teams
- Sicherheitsfunktionen und was es dabei zu beachten gibt
624 pages · Wiley-VCH, July 2026 · German · ISBN 978-3-527-72345-4
Twenty-seven
seconds.
Too short and it's sour. Too long and it's bitter. Everything lies in between. Just like a rollout.
m365 Macchiato.
Once a month I write down what actually mattered in the Message Center, explain one topic properly and recommend a coffee worth drinking.
Email sign-up opens shortly. Until then m365 Macchiato runs on LinkedIn.