receiving the 1004 error code.

I am receiving the 1004 error code.
For wkb_main.Sheets("Index").Select
While using the following code:

Dim FSO As Scripting.FileSystemObject
Dim wkb_main As Workbook
Dim wkb_store_sku As Workbook

Sub GetFilesInFolder()


Dim SourceFolder As Scripting.folder, SubFolder As Scripting.folder
Dim FileItem As Scripting.file
Dim Path_original As String
Dim Temp_path As String
Dim i As Integer
Dim path_and_subfolder_legnth As Integer
Dim path_legnth As Integer
Dim def_path_from_legnth As Integer
Dim R_count As Integer
 Set wkb_main = ThisWorkbook
 wkb_main.Sheets("Index").Select
 Set FSO = New Scripting.FileSystemObject
 Set SourceFolder = FSO.GetFolder(Path_All_36_Still_Photos)

I’m not sure where my mistake is any help will be appreciated.

The answer is yes to both questions.
Any other ideas?

That seems to work thank you
Now I am receiving error Invalid procedure call or argument
for Set SourceFolder = FSO.GetFolder(Path_All_36_Still_Photos)
That seems to work thank you
Now I am receiving error Invalid procedure call or argument
for Set SourceFolder = FSO.GetFolder(Path_All_36_Still_Photos)

Do you have any idea how to solve that one
?