#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?miU)On\s[a-z]{3},\s[0-9]{1,2}\s[a-z]{3,4}\s[0-9]{4}\sat\s[0-9]{1,2}:[0-9]{1,2},\s[^<]*<[a-z0-9._%+\-]+@[a-z0-9.\-]+\.[a-z]{2,6}>\swrote:"
Local $sString = "On Thu, 4 Oct 2018 at 10:48, The Rounds <no-reply+dev@therounds.com> wrote:" & @CRLF & _
"On Sun, 23 Sept 2018 at 09:01, Some Person <cool_guy-123+extra@a.co.uk> wrote:" & @CRLF & _
""
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH)
Local $aFullArray[0]
For $i = 0 To UBound($aArray) -1
_ArrayConcatenate($aFullArray, $aArray[$i])
Next
$aArray = $aFullArray
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm