<Directory "C:\xampp\htdocs">
Options FollowSymlinks ExecCGI
Order allow,deny
Allow from all
DirectoryIndex Default.aspx index.htm index.aspx
</Directory>
This section overrides the
<Directory "C:/xampp/htdocs"> of the DocumentRoot section near the top of the file and should be identical in the Options directive or you will get the error you are getting.
The bold Options entries above should be the same as the
<Directory "C:/xampp/htdocs"> Options below:
<Directory "C:/xampp/htdocs">
#
# Possible values for the Options directive are "None", "All",
# or any combination of:
# Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews
#
# Note that "MultiViews" must be named *explicitly* --- "Options All"
# doesn't give it to you.
#
# The Options directive is both complicated and important. Please see
# http://httpd.apache.org/docs/2.2/mod/core.html#options
# for more information. #
Options Indexes FollowSymLinks Includes ExecCGI
Also
DirectoryIndex Default.aspx index.htm index.aspx does not contain
index.php or
index.html and so those files will not be served if they are found in the htdocs directory or it's sub directories as the default index file.
They appear to have been added by a Microsoft process as both those files are foreign to Microsoft and so unrecognizable but recognizable to Apache and are needed for the Apache server - they are in an Apache server directory not the Microsoft .Net directory.
Be very vigilant when Microsoft modifies any configuration file as they really don't have much of a clue when it comes to all things Apache etc.
You have to be very careful when modifying the httpd.conf file as subsequent or later entries override previous or earlier entries, which has occurred in your case.
Fix the above entries and it should fix those errors, then save the file and restart apache - always make a backup of conf and ini files before editing.