Und hier noch ne Variante, falls die *.txt unterhalb eines Startpfades in diversen Ordnern liegen, also rekursiv gesucht werden müssen.
Spoiler anzeigen
Dim $Pfad_txt = "C:\Files" ; Startpfad für rekursive Suche nach TXT-Files
Dim $Pfad_Backup = "C:\Backup\" ; Wurzelpfad für Sicherungen
Dim $SaveDir
Dim $arTXT ; Array mit den ermittelten TXT-Files
$arTXT = _GetFileList($Pfad_txt, "*.txt")
If IsArray($arTXT) Then
$SaveDir = DirCreate($Pfad_Backup & @YEAR & "-" & @MON & "-" & @MDAY)
For $i = 1 To $arTXT[0]
$var = StringSplit($arTXT[$i], "\")
FileMove($arTXT[$i], $SaveDir & "\" & $var[$var[0]]) ; Datei in Backupordner verschieben
Next
EndIf
; AutoIt Version: 3.0
; Language: English
; Platform: Win9x/NT/XP
; Author: jos van der Zande
;
; Find files in directory and subdirectories and return it in an Array, all coded in Autoit3
;
; _GetFileList($DIR, $FILEMASK, 1) ; _GetFileList($DIR, $FILEMASK [, Flag]) Flag GetFile(Default) = 0 , GetDirOnly = 1
;********************************************************************************
;Recursive search for filemask
;********************************************************************************
Func _GetFileList($T_DIR,$T_MASK,$DIR_ONLY=0)
Dim $N_DIRNAMES[200000] ; max number of directories that can be scanned
Local $N_DIRCOUNT = 0
Local $N_FILE
Local $N_SEARCH
Local $N_TFILE
Local $N_OFILE
Local $T_FILENAMES
Local $T_FILECOUNT
Local $T_DIRCOUNT = 1
Local $FILEMASK
; check Filemask \ for empty File-Array by GetDirOnly
If $FILEMASK = "n" Then $FILEMASK = "*.no"
; remove the end \ If specified
If StringRight($T_DIR,1) = "\" Then $T_DIR = StringTrimRight($T_DIR,1)
$N_DIRNAMES[$T_DIRCOUNT] = $T_DIR
; Exit if base dir doesn't exists
If Not FileExists($T_DIR) Then Return 0
; keep on looping until all directories are scanned
While $T_DIRCOUNT > $N_DIRCOUNT
$N_DIRCOUNT = $N_DIRCOUNT + 1
; find all subdirs in this directory and save them in a array
$N_SEARCH = FileFindFirstFile($N_DIRNAMES[$N_DIRCOUNT] & "\*.*")
While 1
$N_FILE = FileFindNextFile($N_SEARCH)
If @error Then ExitLoop
; skip these references
If $N_FILE = "." Or $N_FILE = ".." Then ContinueLoop
$N_TFILE = $N_DIRNAMES[$N_DIRCOUNT] & "\" & $N_FILE
; if Directory than add to the list of directories to be processed
If StringInStr(FileGetAttrib( $N_TFILE ),"D") > 0 Then
$T_DIRCOUNT = $T_DIRCOUNT + 1
$N_DIRNAMES[$T_DIRCOUNT] = $N_TFILE
EndIf
Wend
FileClose($N_SEARCH) ; find all Files that mtach the MASK
$N_SEARCH = FileFindFirstFile($N_DIRNAMES[$N_DIRCOUNT] & "\" & $T_MASK )
If $N_SEARCH = -1 Then ContinueLoop
While 1
$N_FILE = FileFindNextFile($N_SEARCH)
If @error Then ExitLoop
; skip these references
If $N_FILE = "." Or $N_FILE = ".." Then ContinueLoop
$N_TFILE = $N_DIRNAMES[$N_DIRCOUNT] & "\" & $N_FILE
; if Directory than add to the list of directories to be processed
If StringInStr(FileGetAttrib( $N_TFILE ),"D") = 0 Then
$T_FILENAMES = $T_FILENAMES & $N_TFILE & @CR
$T_FILECOUNT = $T_FILECOUNT + 1
;MsgBox(0,'filecount ' & $T_FILECOUNT ,$N_TFILE)
EndIf
Wend
FileClose($N_SEARCH)
Wend
If $DIR_ONLY = 0 Then
$T_FILENAMES = StringTrimRight($T_FILENAMES,1)
$N_OFILE = StringSplit($T_FILENAMES,@CR)
Return( $N_OFILE )
Else
ReDim $N_DIRNAMES[$N_DIRCOUNT+1]
$N_DIRNAMES[0] = $N_DIRCOUNT
Return $N_DIRNAMES
EndIf
EndFunc ;==>_GetFileList
EDIT:
Man soll nicht unbedingt nach 12 Std. Arbeit versuchen Programmierprobleme zu lösen 
, da war ich etwas unaufmerksam und ein Fehler hat sich eingeschlichen.
Hab ihn hiermit geBugFixt 
