>> C21 file

C21 file format description

Many people share .c21 files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .c21 file can be edited, converted or printed with. On this page, we try to provide assistance for handling .c21 files.

1 filename extension(s) found in our database.

.c21 - CARE-S InfoWorks Defined Pollutant Detail Data

The C21 data files are related to CARE-S. C21 file is a CARE-S InfoWorks Defined Pollutant Detail Data. Computer-Aided Rehabilitation Program for Sewers (CARE-S) is a software program that supports efficiency in rehabilitation decisions.

Data files
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CARE-S InfoWorks Defined Pollutant Detail Data related extensions:
CARE-S InfoWorks Biochemical Oxygen Detail Data
CARE-S InfoWorks Phosphorus Detail Data
CARE-S InfoWorks Catchment Runoff Data
CARE-S InfoWorks Nodes Data
CARE-S Depth Hydrographs for Gauged Pipes
CARE-S InfoWorks Land Use Data

Naturally, other applications may also use the .c21 file extension. Even harmful programs can create .c21 files. Be especially cautious with .c21 files coming from an unknown source!

Can't open a .c21 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 .c21 file extension is often given incorrectly!

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

21, ce1, c2l, cw1, c2w

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

Cybernet v2 Document
ComputerEyes Raw Image
Creeper World Game Map Data
POV-Ray Include File

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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