Can't run icacls to a directory with spaces

Question

I'm trying to run a simple icacls to a directory on my computer and I'm facing this error:

PS C:\Users\gguer\Documents> icacls.exe '.\My Digital Editions\'
.\My Digital Editions": The filename, directory name, or volume label syntax is incorrect.
Successfully processed 0 files; Failed processing 1 files

I'm using single quotes to escape the spaces as I was thought, so I don't know what is the issue here. Hope you can help me. Thanks!

Answer 1

Solved. Just had to remove the last backslash. Cheers.

Answer 2

To add an explanation to your own effective workaround (not including a trailing \ in your argument):

What you're seeing is a bug in Windows PowerShell with respect to how it passes arguments to external programs - this problem has been fixed in PowerShell (Core) 7+ .

Behind the scenes, PowerShell (of necessity) translates your single -quoted argument containing spaces to a double -quoted form, because external CLIs can only be assumed to understand "..." quoting.

The command-line parsing rules used by most CLIs consider the sequence \" to be an escaped " character, ie a " character to be considered a verbatim part of the argument rather than delimiting it.

Therefore, a verbatim \ at the end of a double-quoted string must itself be escaped as \\ in order to be recognized as such - this is what Windows PowerShell neglects to do :

That is, Windows PowerShell translates your call as follows:

# Resulting command line as used behind the scenes for actual invocation.
# WinPS: BROKEN, because the \ at the end isn't escaped.
icacls.exe ".\My Digital Editions\"

When icacls.exe parses this command line, it sees verbatim .\My Digital Editions" (note the verbatim " at the end), as reflected in the error message.

PowerShell (Core), by contrast, does perform the necessary escaping:

# Resulting command line as used behind the scenes for actual invocation.
# PowerShell (Core): OK
icacls.exe ".\My Digital Editions\\"

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As an aside:

A related bug that affects how " embedded in arguments are passed to external programs is still present in PowerShell (Core) as of 7.2.x - see this answer .