Podes ir con filesystemobject recorriendo
dim fs as scripting.filesystemobject
dim ex as excel.application
dim a as scripting.file
for each a in fs.getfolder(path).files
if right(a.name,3) = "xls" then
ex.workbooks.open(a.path)
y ahi trabajar con el excel
luego lo cerras y seguis dando vueltas
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