[SOLVED] How to fix curl syntax error in Windows Powershell?

Issue

I'm trying to use curl in Windows Powershell to download a file from an SFTP/FTPS site, I have tried to follow the examples in href="https://4sysops.com/archives/how-to-use-curl-on-windows/" rel="nofollow noreferrer">How to use curl on Windows, which seem to indicate that I can download from an SFTP/FTPS site. I do the following:

PS C:\temp> curl -User 'username:password' -Uri 'ftp://ftp.company.com/devops/path/somefile.txt' -OutFile somefile.txt

But I get the following error

curl : The remote server returned an error: (530) Not logged in.
At line:1 char:1
+ curl -User 'username:password' -Uri 'ftp://ftp.company.com/devops ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (System.Net.FtpWebRequest:FtpWebRequest) [Invoke-WebRequest], W
   ebException
    + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestComma
   nd

I've also tried ideas in other Stackoverflow posts, e.g., How to use the curl command in PowerShell?, to no avail. What is my syntax error?

Solution

Building on the helpful comments:

• In Windows PowerShell (but no longer in PowerShell (Core) 7+) curl is built-in alias of Invoke-WebRequest, whose syntax is very different from that of curl.exe.

  • To reliably invoke the latter on Windows, invoke it with .exe (curl.exe ...)

  • curl.exe ships with Windows since Windows 10 / Windows Server 2019.

• Your attempt ended up calling Invoke-WebRequest, as evidenced by the error message you saw.

  • While your call technically fulfills the syntax requirements of Invoke-WebRequest, it cannot work as intended:

    • -User, thanks to PowerShell's "elastic syntax", prefix-matched the -UserAgent parameter, which is not your intent.

    • Since no credentials were actually passed (which would require the -Credential parameter), you received the error you saw.

---

Therefore, you have two options:

• Stick with Invoke-WebRequest and use its parameters properly.

  • However, given that FTP support has been removed from Invoke-WebRequest in PowerShell (Core) 7+, perhaps using curl.exe is better (see next point).

• Switch to curl.exe and use its parameters properly; e.g.:

  curl.exe -u 'username:password' ftp://ftp.company.com/devops/path/somefile.txt -o somefile.txt
  

Answered By - mklement0

Answer Checked By - Timothy Miller (WPSolving Admin)