Function Convert-WMITime{
param([string]$WMITime)

$yr=[string]$WMITime.Substring(0,4)
$mo=[string]$WMITime.substring(4,2)
$dy=[string]$WMITime.substring(6,2)
$tm=[string]$WMITime.substring(8,6)
$hr=[string]$tm.Substring(0,2)
$min=[string]$tm.substring(2,2)
$sec=[string]$tm.substring(4,2)
#create string
$s="$mo/$dy/$yr "+$hr+":"+$min+":"+$sec
#cast result as DateTime type
$result=[DateTime]$s
return $result
}

$t="20070214115312.491614-300"
Convert-wmitime $t