Installation fails when server password contains double quote

[dkattan]

You probably should build up the Arguments using a string array and pass them to Start-Process so it can properly escape them.

$Arguments = @()
$Arguments += "/i"
$Arguments += $InstallerFilePath
$Arguments += "/qn"
if($ServerPassword)
{
   $Arguments += $ServerPassword
}

Start-Process -Wait msiexec -ArgumentList $Arguments

LabTech-Powershell-Module/LabTech.psm1

Line 1292 in 69988bc

$(If ($ServerPassword -and $ServerPassword -match '.') {"SERVERPASS=""$ServerPassword"""} Else {""}),

[DarrenWhite99]

It is building an argument list, but it is joining them all together immediately. ( -join ' ' ) .
But the password alone is not the argument, it is SERVERPASS=PASSWORD .. I don't know if you can get away with SERVERPASS= PASSWORD as two arguments.

[dkattan]

Upon further inspection, the problem is more about escaping double quotes in MSI parameters, and not escaping them for the command line.

$ServerPassword = 'Hello"world'
"SERVERPASS=""$ServerPassword"""

SERVERPASS="Hello"world"

This makes msiexec unable to parse the command line, and if we were to be in an interactive session, pops up the help dialog.

I think the solution instead is a $ServerPassword = $ServerPassword.Replace('"','""') on the preceding line

As an aside, TIL I put entirely too much faith in Start-Process handling of -ArgumentList when it is an array.

https://github.com/PowerShell/PowerShell/blob/9f1f6762073e450d0940cfcbe8ee6dbb8710ea08/src/Microsoft.PowerShell.Commands.Management/commands/management/Process.cs#L1876

I naively assumed it was scanning for spaces in each array item and wrapping it in double quotes if found.

This is not the case.

Start-Process -Wait msiexec -ArgumentList "/i","C:\Mimecast for Outlook 7.9.0.79 (x64).msi","/qn"

Fails in the same mode as above, however

Start-Process -Wait msiexec -ArgumentList "/i","`"C:\Mimecast for Outlook 7.9.0.79 (x64).msi`"","/qn"

Works as expected.

[DarrenWhite99]

Resolved by pull #58