powershell does not recognize the path environment variable

Hi, I am running powershell in ws2012 r2 version and when i attempted to run executable whose path is defined in the env:path variable, it can not run. Here is the output. How do I make the path recognizable in powershell so I dont have to type full command. I hope and presume it is something very simple, but I am not able to find information regarding this online. Here is the output from dos prompt in which executable runs and loading of powershell after that executabe are no longer found:

(c) 2013 Microsoft Corporation. All rights reserved.

C:\Windows\system32>signtool

SignTool Error: A required parameter is missing.

Usage: signtool <command> [options]

       Valid commands:

               sign       --  Sign files using an embedded signature.

               timestamp  --  Timestamp previously-signed files.

               verify     --  Verify embedded or catalog signatures.

               catdb      -- Modify a catalog database.

               remove     --  Reduce the size of an embedded signed file.

For help on a specific command, enter "signtool <command> /?"

C:\Windows\system32>powershell

Windows PowerShell

Copyright (C) 2013 Microsoft Corporation. All rights reserved.

PS C:\Windows\system32> signtool

signtool : The term 'signtool' 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

+ signtool

+ ~~~~~~~~

   + CategoryInfo         : ObjectNotFound: (signtool:String) [], CommandNot

  FoundException

   + FullyQualifiedErrorId : CommandNotFoundException

PS C:\Windows\system32>