>> DEFS file

DEFS file format description

Many people share .defs files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .defs file can be edited, converted or printed with. On this page, we try to provide assistance for handling .defs files.

1 filename extension(s) found in our database.

.defs - BlueJ Settings File

The DEFS development files are related to BlueJ. DEFS file is a BlueJ Settings File. BlueJ is an integrated development environment (IDE) for the Java programming language, developed mainly for educational purposes, but also suitable for small-scale software development.

Development files
- / -
BlueJ Settings File related extensions:
BlueJ Package
BlueJ Context File
BlueJ Template File

Naturally, other applications may also use the .defs file extension. Even harmful programs can create .defs files. Be especially cautious with .defs files coming from an unknown source!

Can't open a .defs file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following message:

Windows can't open this file:


To open this file, Windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually select one from a list of programs that are installed on your computer.

To avoid this error, you need to set the file association correctly.

The .defs file extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

def, efs, des, refs, dfs

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

C++ Definition File
SQ-80 Sample
Binary Editor Definition Data
Kryptel Filesets File
Intuit QuickBooks Template
Resilient File System Image

Operating systems

DataTypes.net currently supports the following operating systems:

Windows XP/Vista, Windows 7/8, Windows 10, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, Mac OS X, iOS, Android

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