assoc
By robinharwood
Archived: 2026-04-05 18:37:46 UTC
Displays or modifies file name extension associations. If used without parameters, assoc displays a list of all the
current file name extension associations.
Note
This command is only supported within cmd.exe and is not available from PowerShell. Though you can use cmd
/c assoc as a workaround.
Syntax
assoc [<.[ext]>[=[<filetype>]]]
Parameters
Parameter Description
<.ext> Specifies the file name extension.
<filetype> Specifies the file type to associate with the specified file name extension.
/? Displays help at the command prompt.
Remarks
To make changes in associations, you need administrator privileges.
To remove the file type association for a file name extension, add a white space after the equal sign by
pressing the SPACEBAR.
To associate files without extension to a file type, use just a dot (see the examples).
To view current file types that have open command strings defined, use the ftype command.
To redirect the output of assoc to a text file, use the > redirection operator.
Examples
To view the current file type association for the file name extension .txt, type:
https://docs.microsoft.com/windows-server/administration/windows-commands/assoc
Page 1 of 2

assoc .txt
To remove the file type association for the file name extension .bak, type:
assoc .bak=
Note
Make sure you add a space after the equal sign.
To view the output of assoc one screen at a time, type:
assoc | more
To send the output of assoc to the file assoc.txt, type:
assoc>assoc.txt
Associate .log to text files:
assoc .log=txtfile
Associate files with no extension to text files:
assoc .=txtfile
Related links
Command-Line Syntax Key
ftype command
Source: https://docs.microsoft.com/windows-server/administration/windows-commands/assoc
https://docs.microsoft.com/windows-server/administration/windows-commands/assoc
Page 2 of 2