Disable line "AddModule mod_autoindex.c" in your httpd.conf
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#
# Reconstruction of the complete module list from all available modules
# (static and shared ones) to achieve correct module execution order.
#
# The modules listed below, without a corresponding LoadModule directive,
# are static bound into the standard Apache binary distribution for Windows.
#
# Note: The order in which modules are loaded is important. Don't change
# the order below without expert advice.
#
# [WHENEVER YOU CHANGE THE LOADMODULE SECTION ABOVE, UPDATE THIS TOO!]
ClearModuleList
#AddModule mod_vhost_alias.c
AddModule mod_env.c
AddModule mod_log_config.c
#AddModule mod_mime_magic.c
AddModule mod_mime.c
AddModule mod_negotiation.c
AddModule mod_status.c
AddModule mod_info.c
AddModule mod_include.c
# Disable following line with #
#AddModule mod_autoindex.c
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