With the relevant part of the variable:

$Details = "Requested Item
Number"

And the code:

$DetailStartPositionMatches = [regex]::match($Details,"Requested\ Item\s+Number")

write-host "`$DetailStartPositionMatches.success = `"$($DetailStartPositionMatches.success)`""

if($DetailStartPositionMatches.success)
{
  write-host "`$match = `"$match`"" (have also tried $($match)

  $DetailStartPosition = $match.index
}
else
{
  write-host "no match"
}

write-host "`$DetailStartPosition = `"$DetailStartPosition`""

I get the output:

$DetailStartPositionMatches.success = "True"
$match = ""
$DetailStartPosition = ""

Of course...

$Details.indexof("Requested\ Item\s+Number")

...gives me the index fine.

What is wrong with the regex/data such I can't get the index from this code?