Invoke-VMScript: Do not confirm/re-enter guest credentials - powershell

Question

I'm performing an audit on VMs in our environment, and using Invoke-VMScript to get disk info:
$vmErrors = New-Object System.Collections.Generic.List[System.Object]
$report = foreach ($VM in $VMs){
$name = $vm.Name
Write-Host "Retrieving data for $name... " -NoNewline
try{
$output = Invoke-VMScript -ScriptText #'
Get-Disk | Foreach-Object{
[PSCustomObject]#{
ComputerName = $env:COMPUTERNAME
Number = $_.number
Size = [int]($_.size/1GB)
PartitionStyle = $_.PartitionStyle
}
} | ConvertTo-Csv -NoTypeInformation
'# -VM $name -GuestUser $Username -GuestPassword $Password -WarningAction SilentlyContinue -ErrorAction Stop
if($output.ScriptOutput -match 'PartitionStyle')
{
$output.ScriptOutput -replace '(?s)^.+(?="Com)' | ConvertFrom-Csv
}
Write-Host "Done" -ForegroundColor Green
}catch{
$vmErrors.Add($name)
Write-Host "Error!" -ForegroundColor Red
}
}
When running the code in Powershell ISE, I do not need to confirm the credentials for each VM and the script loops perfectly fine, however if I run the script in a standard Powershell window, for each VM I have to enter the username and password for each VM (the credentials will always be the same as what I use to authenticate with the vCenter server.
Example:
Retrieving data for VM NAME...
Specify Credential
Please specify guest credential
User:
How can I run this in a normal window and avoid having to re-enter my credentials each time?
Edit
Example of setting username & password:
$Username = ""
$Password = ""
Function GetUser{
do{
$global:Username = Read-Host "What is your username? (DOMAIN\Username)"
}while($global:Username -eq "")
}
Function GetPassword{
do{
$global:Password = Read-Host "What is your password?" -AsSecureString
$global:Password = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($global:Password))
}while($global:Password -eq "")
}

Answer 1

Solved by changing the credential references in Invoke-VMScript to use $global:Username and $global:Password