Claus-Stefan Duffner

Graduate computer scientist, online business mentor

Claus-Stefan Duffner
4.99 out of 5
Excellent
21 Reviews
Contact information
Claus-Stefan Duffner is a digital business mentor and founder of ISDD GmbH. He has been helping people and companies to build their scalable digital online business for over 25 years. As a graduate computer scientist, he knows the technical side...

Contact information

Claus-Stefan Duffner
Ulimited Dream Life LLC
530B Harkle Rd STE 100
Santa Fe, New Mexico (NM) 87505
United States of America
Directions

100% Recommended
5 stars 21
4 stars 0
3 stars 0
2 stars 0
1 star 0
Customer service
Excellent (5.00)
Cost/Benefit
Excellent (4.95)

21 Reviews on ProvenExpert.com

4.99 out of 5
Excellent
5.00 out of 5
Excellent
Recommendation
In only about 3 months I had a finished product, an online course. What an intensive time! Many thanks for your support, dear Claus-Stefan! Without you, I would never have dared to try it and, as a beginner, I learned an incredible amount! For me, it was a time of constantly pushing my own boundaries and sometimes I still shake myself to believe it. You were able to pick me up well and thank you very much for the great time!
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Customer review & rating for:
Claus-Stefan Duffner
03/27/2024Beatrix L.
5.00 out of 5
Excellent
Recommendation
Klaus-Stefan and his wonderful wife are both way ahead of their time and are already living a life in the absolute abundance matrix. I am always amazed at how valuable their mentoring sessions are and admire their freedom and openness. They are 2 professionals, each in their own field!
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Customer review & rating for:
Claus-Stefan Duffner
03/25/2024Insha B.
5.00 out of 5
Excellent
Recommendation
The courses are engaging and informative, yet understandable.
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Customer review & rating for:
Claus-Stefan Duffner
03/20/2024M.
5.00 out of 5
Excellent
Recommendation
Claus-Stefan Duffner's conferences, courses and offers are full of valuable content. I always enjoy attending them and take a lot away from the wide range of offers.
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Customer review & rating for:
Claus-Stefan Duffner
03/19/2024Silja R.
5.00 out of 5
Excellent
Recommendation
In the mentoring sessions, I learned how to successfully switch from offline to online business. Within a few months, I was laced into visibility. I learned how to create landing pages and funnels. Claus-Stefan showed me everything to do with technology. Carmen accompanied me when doubts and fears arose. Thanks to her, I learned to focus and sell with love. What a power duo !!!!I have more than achieved my goals!!! I now give online webinars, produce products about meridian tapping, give mentoring sessions.
Fear turned into fun and success:

Thanks to you I am living my dream
Thanks to you, I am living my soul business
Thanks to you, I can see that anything is possible
.....I just have to go for it!!!
Thank you dear ones, you are wonderful!!!
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Customer review & rating for:
Claus-Stefan Duffner
03/19/2024Ewa van den B.
5.00 out of 5
Excellent
Recommendation
From 0 to 1000, you could say. Claus-Stefan led me to a 100% realization of a top congress. His mentoring is almost breathtaking, as he was always there for me. And I also enjoy working at night and in the very early hours of the morning. Claus-Stefan always answered my questions, even at the weekend and even when he was traveling. In addition, every question I asked was handled with the utmost care. So if there is anyone I can recommend as a mentor, it is Claus-Stefan Duffner.
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Customer review & rating for:
Claus-Stefan Duffner
01/21/2024M.
5.00 out of 5
Excellent
Recommendation
Very competent and helpful. He has an enormous amount of knowledge and conveys it in an easily understandable way.
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Customer review & rating for:
Claus-Stefan Duffner
01/15/2024M.
5.00 out of 5
Excellent
Recommendation
I don't have an online business at the moment, but I will contact you later if I need to and take advantage of your offers!
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Customer review & rating for:
Claus-Stefan Duffner
01/03/2024Anonymously
5.00 out of 5
Excellent
Recommendation
Thank you, Claus-Stefan, for mentoring me over the past few months. We discussed the planning and implementation of my first online congress together, which gave me more visibility and reach. We also discussed technical questions, e.g. about the Click Summits congress platform, Vimeo, Canva, Digistore24. There were also some tips on technical devices such as the microphone. In addition, I received further helpful impulses for my still quite new online business. I found the mentoring really enriching and can wholeheartedly recommend it. Dr. Sabrina Bechler
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Customer review & rating for:
Claus-Stefan Duffner
12/19/2023Dr. Sabrina B.
5.00 out of 5
Excellent
Recommendation
Very competent and empathetic
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Customer review & rating for:
Claus-Stefan Duffner
12/11/2023Anonymously
5.00 out of 5
Excellent
Recommendation
The Digital Heart Business Academy is a real blessing for anyone who wants to gain a foothold in online business. Claus-Stefan Duffner's program makes you feel well looked after and competently advised. The combination of practical tips and a supportive community makes the learning process enjoyable and effective. I am enthusiastic about the clarity and structure of the program and can recommend it to anyone who wants to realize their online business ideas.
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Customer review & rating for:
Claus-Stefan Duffner
12/11/2023Chee F.
5.00 out of 5
Excellent
Recommendation
Wow, that's what I call an instructive course. Thank you so much Claus-Stefan for YOUR great work. Even though I already knew a lot, I am totally grateful for the wonderful tips. For example, I now understand search engine optimization better, I was particularly impressed by how to get visitors from Instagram to my site, how easily I can protect my site and much more. What I liked best was that YOU, Claus-Stefan, don't beat around the bush, but always get to the point and keep the various lessons very short and concise. The lessons can be implemented immediately in parallel and so you can optimize your website very quickly and easily. You can also divide the course up well and incorporate it wonderfully into your work. TOP!!! I can only say THANK YOU Claus-Stefan, for me YOUR course "The best plugins for YOUR WordPress website" has paid off in many ways. I would love more of such helpful, instructive and easily digestible information. Everything, everything, everything love and continued success on all levels.
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Customer review & rating for:
Claus-Stefan Duffner
12/06/2021Ines K.
4.80 out of 5
Excellent
Recommendation
I really enjoyed the Facebook Booster online course. I now understand the connections and have already been able to put some things into practice.
I give you 5 out of 5 stars. Thank you very much!
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Customer review & rating for:
Claus-Stefan Duffner
08/19/2021Doris Schwär - Karma Therapeuthin nach Dragica Schadegg - d.
5.00 out of 5
Excellent
Recommendation
I found a very good and competent contact person in you. It was coaching at eye level. I really liked the fact that I was able to shape the coaching at my own pace and exactly according to my needs. I developed a sense of ease and joy when it came to digitalization. I have grown with it, have an overview of what is possible and what I still want to implement. I now have the right basis with the right development potential. Your Facebook posts also provide good inspiration. That makes me happy. Thank you for that. I will be happy to come back to you if needed.
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Customer review & rating for:
Claus-Stefan Duffner
08/19/2021Elvira Littner, m.
5.00 out of 5
Excellent
Recommendation
Dear Claus-Stefan,
I immediately felt that I was in good hands with you because I realized that you put your whole heart into your work and that you simply love your vocation. That, coupled with your professionalism and patience, really adds value for customers.

I am deeply grateful for the valuable program because it has helped me to grow digitally and mentally.

5 out of 5 stars - I can really recommend working with Claus-Stefan to anyone.
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Customer review & rating for:
mel@melaniekook.de
01/14/2021Melanie Kook – Expertin für Blockadenlösung – Zentrum Gesundes L.
5.00 out of 5
Excellent
Recommendation
For me and our company, it was necessary to book a professional for the adaptation to digitalization. We made the right choice with Claus-Stefan. With warmth and empathy, we were accompanied over several months and professionally guided to our goal. We still use Claus-Stefan's know-how today and are always delighted with the friendly cooperation.
With best recommendation from Sandro Simon Aeschbach, Passiflora Gesundheit & Therapie GmbH, Switzerland
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Customer review & rating for:
Claus-Stefan Duffner
01/01/2021Sandro Simon Aeschbach Passiflora Gesundheit & Therapie GmbH, S.
5.00 out of 5
Excellent
Recommendation
Wow, and many thanks to Claus-Stefan Duffner. In just under four weeks, he helped me to create my website in a "miraculous" way. Always motivating and with heavenly patience and empathy, he guided me and got me to where I am now.
Claus-Stefan, you get 5 out of 5 stars from me....gerne again.
Thank you from the bottom of my heart 💞
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Customer review & rating for:
Claus-Stefan Duffner
12/25/2020Karin Dold, Energie- und G.
5.00 out of 5
Excellent
Recommendation
Claus-Stefan is an excellent consultant with many great approaches and know-how. My digital presence is better than ever, which is also clearly noticeable in my sales. A clear recommendation!
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Customer review & rating for:
Claus-Stefan Duffner
07/04/2020T.
5.00 out of 5
Excellent
Recommendation
Claus - Stefan Duffner, convinced me with his friendly, reliable and open manner, his factual competence and solution-oriented work, I found very valuable and helpful.
Bettina from Hanover
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Customer review & rating for:
Claus-Stefan Duffner
06/08/2020Bettina aus H.
5.00 out of 5
Excellent
Recommendation
Stefan is a great consultant and skillfully translates wishes into strategies. He works with a lot of empathy and expertise until the customer is 100% satisfied.
I can highly recommend working with him, he takes your business to the next level.
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Customer review & rating for:
Claus-Stefan Duffner
05/23/2020A.
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All reviews and experiences about Claus-Stefan Duffner are the subjective opinions of those who compose and submit them  |  The profile owner is responsible for the contents of this page  |   Profile active since 05/15/2020  |  Last update: 03/27/2024   |  Report profile

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