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File crashes Excel!!

Save my workbook!
The best tool for salvaging problematic workbooks.


Excel VBA Masterclass (English)
Excel VBA for Financials (Dutch)

Third party tools

Speed up your file

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)

Our Amsterdam Excel Summit was great
Our Amsterdam Excel Summit has been a great success. We had two very well received days full of Excel and Power BI sessions. I've added photo two links to impressions.
Tue, 25 Apr 2017 10:40:00 GMT

Update: Excel File Remediation Utility
Our Excel File Remediation Utility has just been updated. I have added an option to remove all styles from the workbooks. This is very useful if you have Excel files with corrupt styles.
Thu, 23 Mar 2017 15:40:00 GMT

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. Added jump to pivotsource when you trace precedents when in a pivottable.
Fri, 03 Mar 2017 13:00:00 GMT

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. Fixed issue regarding range names in formulas.
Sun, 19 Feb 2017 13:20:00 GMT

Update to Flexfind
Updated: Flexfind. Added support for replacing in Powerquery M code (Excel 2016).
Sat, 18 Feb 2017 19:10:00 GMT

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. Fixed issue with short-cut keys not responding immediately after openening Excel.
Wed, 15 Feb 2017 07:50:00 GMT

Update: RefTreeAnalyser
RefTreeAnalyser 2.0 has just been updated. I have fixed a bug, Pivottables were not listed when pointing to a table name.
Thu, 9 Feb 2017 09:45:00 GMT

The Amsterdam Excel Summit 2017: Registration is open
Come and join us in Amsterdam on April 18 and 19 2017 for our famous Amsterdam Excel Summit. We have just opened registration so make sure you book your seats before Feb 20 and receive a nice early-bird discount! Visit the Amsterdam Excel Summit Website
Mon, 16 Jan 2017 16:20:00 GMT