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Check out our RefTreeAnalyser
the ultimate Excel formula auditing tool.


Excel VBA for Financials (Dutch)

Third party tools

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The best tool to optimise your Excel model!

Repair your file

Stellar Phoenix Excel Repair
Best tool to repair corrupt Excel sheets and objects

Your Excel Expert; uw Excel specialist

Welcome to the website of

JKP Application Development Services.

If you are looking for an Excel specialist and an Excel and VBA expert you've come to the right place.

My core business is developing solutions using Microsoft Excel/VBA and Access/VBA. Integration with other (Office) programs is possible.

Need expert Excel help? Get in touch.

My Services page lists some example projects.

Need Excel or VBA training? Information about our Excel and VBA trainings can be found on our trainings page.

If you need more information about me, look at my English homepage.

To find out whether you've actually found an Excel expert, I invite you to browse through my Excel articles.

I also recommend to try my free utilities.

Click here for remote assistanceClick for remote assistance

Welkom op de website van

JKP Application Development Services.

Als u op zoek bent naar een echte Excel specialist en een Excel en VBA expert dan bent u aan het juiste adres.

De nadruk ligt op het ontwikkelen van toepassingen in Microsoft Excel/VBA en Microsoft Access/VBA. Ook integratie met andere (Office) programma's is mogelijk.

Kunt u de hulp van een Excel expert gebruiken? Neem dan contact op.

Op de Diensten pagina vind u voorbeelden van projecten.

Zoekt u Excel of VBA cursussen? Informatie over onze Excel en VBA trainingen kunt u op onze training pagina vinden.

Wilt u meer over mij weten ga dan naar mijn Nederlandse homepage.

Wilt u zelf beoordelen of u een echte Excel expert heeft gevonden, bekijk dan mijn Excel artikelen.

Probeer ook eens mijn gratis hulpprogramma's.

Klik hier voor hulp op afstandKlik voor hulp of afstand


What's new on this site:

(English and/or Dutch content)

Nieuw op deze site

(Engelse en/of Nederlandse artikelen)

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. I Improved the performance of finding dependents and improved how Objects are listed.
Wed, 25 Nov 2015 11:35:00 GMT

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. I fixed a small bug causing a runtime error when you close Excel.
Wed, 07 Oct 2015 20:30:00 GMT

Tool to help close all Excel windows
With the new MDI interface introduced with Excel 2013, closing all workbooks has become unnecessary difficult. This little addin adds a 'Quit Excel' button to your File menu that will close all open workbooks and quit Excel. It also features a Short-cut key: control+q
Thu, 01 Oct 2015 09:30:00 GMT

Celebrating 30 years of Excel with 30 days 30% discount!
To celebrate the fact that Excel was launched 30 years ago (September 30, 1985) we're having an anniversary sale at From September 30 to October 30, 2015 we offer a 30 % discount on both our products: RefTreeAnalyser and The ...
Thu, 01 Oct 2015 08:50:00 GMT

Solving problems with Office caused by Windows 10
I have just added a new chapter to my article on solving startup problems in Excel, especially for the people who are experiencing issues after upgrading their computer to Windows 10
Wed, 16 Sep 2015 13:35:00 GMT

Update to Flexfind
Updated: Flexfind. I have recently fixed a bug in Flexfind where the tool appears to make Excel 2013 unresponsive. The root cause of the problem was the new MDI interface of Excel which forced us to make the Flexfind window the topmost window, thus causing message boxes to appear behind the window in some situations.
Mon, 14 Sep 2015 10:05:00 GMT

Summer sale at
Yes we're having a summer sale at From July 1 to July 10 we offer a 25 % discount on both our products: RefTreeAnalyser and The Excel File Remediation Utility
Thu, 25 Jun 2015 06:15:00 GMT

New product: The Excel File Remediation Utility
I have launched a new product you can try and buy directly from my site: The Excel File Remediation Utility. This tool helps you to try and salvage Excel models with problematic content accumulated during a long editing history.
Thu, 25 Jun 2015 06:15:00 GMT