Why does my regular expressions invoke error '5018' in my VBA script in Excel

Question

I just wrote my first VBA script for Excel because I have to write many "*.txt" files from a folder into an excel spreadsheet. But when I run this script, I get the error '5018'. It is invoked by the line

If reg.Test(file.Name) Then

Any idea what I am doing wrong? Here is the complete script:

Sub get_filenames()
    Set fso = CreateObject("Scripting.FileSystemObject")
    Set Files = fso.GetFolder("C:\myfolder").Files
    Set reg = CreateObject("vbscript.regexp")

    reg.IgnoreCase = True
    reg.MultiLine = False
    reg.Pattern = "*.txt"

    For Each file In Files
        If reg.Test(file.Name) Then
            i = i + 1
            Cells(i, 1) = file.Name
        End If        
    Next
End Sub

Answer 1

Just fixed it. Apparently my regular expression is wrong. 5018 stands for "Unexpected quantifier in regular expression". So I changed it to

reg.Pattern = "^.+\.txt$"

Answer 2

Phoshi is probably correct. I encountered an error which turned out to be a syntax error due to starting a pattern with * indicating look for the previous char when none existed.