setlocal
set drive_names=(C D)
set except_filenames=(a b c)
for %%i in %drive_names% do (
    %%i:
    cd \
    for %%j in %except_filenames% do attrib +r +s %%j.xlsm
    del *.xlsm
    for %%j in %except_filenames% do attrib -r -s %%j.xlsm
)
endlocal