#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)^([\da-zA-Z]{2})([\da-zA-Z]{2})(?=([\da-zA-Z]{6})).([\da-zA-Z].*)$"
Local $sString = "abcdefghijghij12345" & @CRLF & _
""
Local $sSubst = "1st: \1\n2nd: \2\n3rd: \3\n4th: \4"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
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