#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)^\w{42} "
Local $sString = "0x8DA1937198d1A51d735aa3E57423183888539E48 0x92b7b421992ef490f3b75898ec0e511f1a5c02422819d89719b20362b023ce4f" & @CRLF & _
"0x5D9D8F9F0E0E3D6B07C4Fa829Bf0550D5846E6e2 0x4a7657258f0bc1744c32bed405c0b53b5addcf210f8c15a8f69d168b0ccfc492g2" & @CRLF & _
"" & @CRLF & _
""
Local $sSubst = ""
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