Error when trying to run .bat file using runas Administrator using PowerShell

Try the following:

Start-Process powershell `
   -WorkingDirectory (Split-Path $script) `
   -Credential xxx\xxxvis_desktop `
   -ArgumentList '-noprofile', '-command', "
     & { start-process powershell -ArgumentList '-File', '$script' -Verb RunAs }
     "

• Your primary problem was most likely that the target user - xxx\xxxvis_desktop - lacked permission to access what happened to be the current directory at the time of invocation.

  • Setting the working directory explicitly to a directory the target user is allowed to access should fix that problem - -WorkingDirectory (Split-Path $script) sets the working dir. to the dir. in which the target script is located.

• Your secondary problem - as pointed out in a comment on the question by Matt - is that the command string you passed to Start-Process was enclosed in '...' (single quotes), causing the embedded $script variable reference not to be expanded (interpolated).

  • Using "..." (double quotes) fixes that problem; note, however, that the command line to pass to the powershell executable is split into individual arguments passed via -ArgumentList - the (literal, single-quoted) options, followed by the (interpolated, double-quoted) command string, which is the preferable way to pass arguments, because it is more robust.

  • Note, how the $string reference inside the command string is enclosed in embedded '...' so as to ensure that when the invoked powershell instance parses the command string, the value of $string is recognized as a single argument (although this happens not to be necessary for the value at hand, \\xxxhsfmsl03\adap\Database\Install\AugKA\DEC16.bat).

    • If there's a chance that the value of $script has embedded ' instances, you must use the following (double the ' instances to escape them):
      $($script -replace "'", "''")

• The final problem is that you cannot use Start-Process directly on a script - as in the outer call, you need to call powershell and pass it the script filename as an argument.

Additional notes:

• The & { ... } wrapper around the start-process call in the command string shouldn't be necessary.

• Generally, you could use a single Start-Process call with -Verb RunAs to elevate the run of $script, but, unfortunately, -Verb RunAs and -Credential cannot be combined, so that means:

  • If the current user is an administrative account, the elevated session will invariably run as that user - you'll just get a yes/no prompt to confirm elevation.

  • Otherwise, the credentials will be prompted for, but you cannot pre-populate the username in that dialog.

  • Start-Process -Verb RunAs powershell -ArgumentList '-noprofile', '-File', $script