PowerShell does not recognise external executables

Question

Why cannot I run 7z in the following PowerShell script?

Set-Location "C:\Program Files\7-Zip"
Invoke-Expression "dir"
Invoke-Expression "7z"
Invoke-Expression "7z.exe"

Result:

Directory: C:\Program Files\7-Zip


Mode                LastWriteTime     Length Name                                                                                                                        
----                -------------     ------ ----                                                                                                                        
-a---        11/18/2010   9:08 PM      91020 7-zip.chm                                                                                                                   
-a---        11/18/2010   9:08 PM      86016 7-zip.dll                                                                                                                   
-a---        11/18/2010   9:24 PM    1422336 7z.dll                                                                                                                      
-a---        11/18/2010   9:08 PM     284160 7z.exe                                                                                                                      
-a---        11/18/2010   9:27 PM     162816 7z.sfx                                                                                                                      
-a---        11/18/2010   9:27 PM     152064 7zCon.sfx                                                                                                                   
-a---        11/18/2010   9:10 PM     740352 7zFM.exe                                                                                                                    
-a---        11/18/2010   9:11 PM     387072 7zG.exe                                                                                                                     
-a---         9/10/2010  11:41 AM        333 descript.ion                                                                                                                
-a---        11/18/2010   9:11 PM      32400 History.txt                                                                                                                 
-a---          1/2/2010   3:18 PM       1927 License.txt                                                                                                                 
-a---        11/18/2010   9:12 PM       1565 readme.txt                                                                                                                  
7z : The term '7z' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, 
verify that the path is correct and try again.
At line:1 char:1
+ 7z
+ ~~
    + CategoryInfo          : ObjectNotFound: (7z:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

7z.exe : The term '7z.exe' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was 
included, verify that the path is correct and try again.
At line:1 char:1
+ 7z.exe
+ ~~~~~~
    + CategoryInfo          : ObjectNotFound: (7z.exe:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

7z is a hassle to deal with in powershell. You need to use the & syntax. It's the only way to make it work. — user1751825
– user1751825, Commented May 11, 2016 at 2:54
Check out these uses of & and Start and see if they help solve the problem — LinkBerest - SO sold our work
– LinkBerest - SO sold our work, Commented May 11, 2016 at 2:56
I tried Invoke-Expression "& 7z", but it still gave me an error. Did I use the & correctly? — Damn Vegetables
– Damn Vegetables, Commented May 11, 2016 at 3:03
Because when you are in a folder in PowerShell, you cannot run things in that folder directly unless you specify .\ first, e.g. .\7z.exe. — TessellatingHeckler
– TessellatingHeckler, Commented May 11, 2016 at 3:05
Thank you. Invoke-Expression "./7z" worked. .\7z also worked. — Damn Vegetables
– Damn Vegetables, Commented May 11, 2016 at 3:06

qbik · Accepted Answer · 2016-05-11 03:07:54Z

4

By default, Powershell does look for executables on PATH, but not in current directory (.\). You could:

Preppend ".\" to the name of executable when calling from current directory:
```
Invoke-Expression ".\7z"
```
Call it by full path (using mentioned & syntax):
```
& "c:\Program Files\7-zip\7z"
```

add executable's directory to PATH ($env:Path in Powershell):

$env:Path += "c:\Program Files\7-zip"
Invoke-Expression "7z"

answered May 11, 2016 at 3:07

qbik

6,0082 gold badges31 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Damn Vegetables Over a year ago

If I were to use the third method, is it temporary (only affects that script while the script is running) or is it permanent (the same effect as adding the path in the System Variables dialogue)?

qbik Over a year ago

It is temporary - it modifies PATH variable just for the current process. If you want to make it permanent, use [Environment]::SetEnvironmentVariable (technet.microsoft.com/en-us/library/ff730964.aspx).

Collectives™ on Stack Overflow

PowerShell does not recognise external executables

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related