Welcome to this "Conversion to 4D v16" manual, which describes various points to be checked before, during, and after conversion of a 4D v15 database to 4D v16.

Conversion of 4D v15 databases should go smoothly in 4D v16, and we provide a few recommendations to make sure everything goes well in the "Principles for conversion" chapter. However, once the conversion is done, there are a couple of things to check, such as "New compatibility options" and "Changes in behavior" both at the application level and that of the 4D commands, which you need to understand in order to make the best use of new features in 4Dv16 .

And finally, this manual summarizes deprecated features in 4D v16 that developers needs to spot quickly in order to assess the time needed to set up new functions.

Note: Some modifications listed in this manual when introduced during the 4D v15 "R-release" program.

When converting earlier or even much older databases, it is often necessary to use intermediate versions. And for the various points to check, refer to the conversion documents for previous versions:

• 4D v15: "Conversion to 4D v15" and "Deprecated features in 4D v15 and higher".
• 4D v14: "Conversion to 4D v14" and "Deprecated features 4D v14 and higher".
• 4D v13: "Conversion to 4D v13" and "Deprecated features 4D v13 and higher".
• 4D v12: "Deprecated features 4D v12 and higher" (there was no "Conversion" document for this version).
• 4D v11: "Conversion to 4D v11 SQL".