WordPress sections in htaccess kills FrontPage permissions

I have WordPress running in the public_html directory of my web server (i.e. the primary domain on my account points to this directory). There are subdirectories off of this folder that are for other websites (e.g. /subdomain for the “subdomain.com” website). Some of these websites in subdirectories are edited using FrontPage.

I have found that the .htaccess file in the root, when configured for WP, messes up the FrontPage permissions and makes it impossible to use FrontPage (FrontPage never prompts for authentication and throws a 404 error). From web searches I’ve discovered that others have encountered this problem (e.g. https://my.bluehost.com/cgi/help/375) , but I have not had success implementing the fixes others proposed.

Here are the details:

When this .htaccess file is in the root, FrontPage works fine:

# -FrontPage-

AuthUserFile /home/user/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/user/public_html/_vti_pvt/service.grp


<Limit GET POST>
order deny,allow
deny from all
allow from all
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>

AuthName myrootdomain.com
IndexIgnore .htaccess */.??* *~ *# */HEADER* */README* */_vti*

I would like to have WP sections in this root .htaccess file and tried to put the following .htaccess file in the top-level public_html directory:

#-FrontPage-

AuthUserFile /home/user/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/user/public_html/_vti_pvt/service.grp

<Limit GET POST>
order deny,allow
deny from all
allow from all
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>

AuthName myrootdomain.com
IndexIgnore .htaccess */.??* *~ *# */HEADER* */README* */_vti*

RewriteRule ^subdir-name/.*$ - [PT] 

ErrorDocument 404 /index.html
<files wp-config.php>
order allow,deny
deny from all
</files>
Options +FollowSymLinks
RewriteEngine On
RewriteCond %{QUERY_STRING} (<|%3C).*script.*(>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} GLOBALS(=|[|%[0-9A-Z]{0,2}) [OR]
RewriteCond %{QUERY_STRING} _REQUEST(=|[|%[0-9A-Z]{0,2})
RewriteRule ^(.*)$ index.php [F,L]
<IfModule mod_deflate.c>
AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css application/x-javascript application/xhtml+xml application/xml application/rss+xml application/atom_xml application/x-javascript application/x-httpd-php application/x-httpd-fastphp 
BrowserMatch ^Mozilla/4 gzip-only-text/html
BrowserMatch ^Mozilla/4.0[678] no-gzip
BrowserMatch bMSIE !no-gzip !gzip-only-text/html
</IfModule>
Options -Indexes
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

HOWEVER, when the above .htaccess file with WP components is installed, it breaks FrontPage authentication.

The .htaccess file in my _vti_bin file of “subdomainN” (which is a domain edited by FrontPage) looks like this:

# -FrontPage-

Options +FollowSymlinks

<Limit GET POST>
order deny,allow
deny from all
allow from all
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>
AuthName mydomain.com
AuthUserFile /home/user/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/user/public_html/_vti_pvt/service.grp

… and the .htaccess file in my _vti_aut and _vti_adm subdirectories of subdomain N looks like this:

# -FrontPage-

Options +FollowSymlinks

<Limit GET POST>
order deny,allow
deny from all
allow from all
require group authors administrators
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>
AuthType Passthrough
AuthName myrootdomain.com
AuthUserFile /home/user/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/user/public_html/_vti_pvt/service.grp

Any suggestions on what I need to tweak to get FrontPage authentication to work AND WP components in the .htaccess file?