Hi,

It would be simpler to start with the list in file z, instead of folder
x

'cycle through rows in file z

myworkbook=some_range_from_file_z
mypassword=some_range_from_file_z

Workbook.Open myworkbook 'don't forget to include full path!!!
ActiveWorkbook.Protect Password:=mypassword, Structu=True,
Windows:=False

'next cycle

If you insist on cycling through the folder, you should use
FileScriptingObject, or FSO. Some cool examples can be googled.
Regards,
ManualMan