Okay, you've got my head spinning... :)
One thing that sticks out is in your new .htaccess (current one) there is this line:
RewriteRule ^zencart.*$ https://www.zencartsite.com/ [R=301,L]
What this appears to do is take what may have been your "old" address and convert it to the new zencartsite...
Put it another way, you've got a lot that is/was going on...
If I understand your directories and usage correctly, you previously had zencartsite loaded into a subdirectory, that subdirectory was
referenced by your host using a domain name: so
Old:
othersite -> public_html/ <- .htaccess 1
zencartsite -> public_html/zencart/zencart . com <- .htaccess 2
New:
othersite -> public_html/othersite . com <- .htaccess 4 (little info, but there is one)
zencartsite -> public_html/ <- .htaccess 3
zencartsite is the only site that is ZC, and othersite has nothing to do with it, correct?
I could really go into all of the issues that the current .htaccess appears to present; however, if I have a correct understanding of the
site structure (based on my crude "diagram" above), then this is the basic structure I suggest assuming the .htaccess files in place.
New .htaccess 3:
#suPHP_ConfigPath /home/myusername/public_html/zencartsite.com
<Files 403.shtml>
order allow,deny
allow from all
</Files>
AddHandler application/x-httpd-php53 .php .php5 .php4 .php3
Redirect 301 /contact.shtml https://www.zencartsite.com/index.php?main_page=contact_us
DirectoryIndex index.php index.html
## BEGIN CEON URI MAPPING REWRITE RULE
# Do rewriting ONLY for zencartsite.com
RewriteCond %{HTTP_HOST} ^(www\.)?zencartsite\.com\.?(:80)?$ [NC]
# Don't rewrite any URIs that point to the old zencart folder
RewriteCond %{REQUEST_URI} !^/zencart/ [NC] #<---- When properly used, the zencart folder could have/should have been rewritten using the plugin and not this rewritecond/rewriterule
# Don't rewrite addon domains
RewriteCond %{REQUEST_URI} !^/othersite.com/ [NC]
# Don't rewrite any URIs ending with a file extension (ending with .[xxxxx])
RewriteCond %{REQUEST_URI} !\.[a-z]{2,5}$ [NC]
# Don't rewrite any URIs for some, popular specific file format extensions,
# which are not covered by main file extension condition above
RewriteCond %{REQUEST_URI} !\.(mp3|mp4|h264)$ [NC]
# Don't rewrite any URIs for some specific file format extensions,
# which are not covered by main file extension condition above
# Uncomment the following line to apply this condition! (Remove the # at the start of the next line)
RewriteCond %{REQUEST_URI} !\.(shtml|3gp|3g2|h261|h263|mj2|mjp2|mp4v|mpg4|m1v|m2v|m4u|f4v|m4v|3dml)$ [NC]
# Don't rewrite admin directory
RewriteCond %{REQUEST_URI} !^/myadmin [NC]
# Don't rewrite editors directory
RewriteCond %{REQUEST_URI} !^/editors/ [NC]
# Don't rewrite myimages directory
RewriteCond %{REQUEST_URI} !^/myimages/ [NC]
# Don't rewrite cgi-bin directory
RewriteCond %{REQUEST_URI} !^/cgi-bin/ [NC]
# Don't rewrite elementstrial directory
RewriteCond %{REQUEST_URI} !^/elementstrial/ [NC]
# Don't rewrite logs directory
RewriteCond %{REQUEST_URI} !^/logs/ [NC]
# Handle all other URIs using Zen Cart (its index.php)
RewriteRule .* ./index.php [QSA,L]
## END CEON URI MAPPING REWRITE RULE
It seems that this is all that really is needed based on the content that was identified for the new site with zencartsite as the root.
Now folder discussion? That's a bit of another topic, but... There are two folder structures that could be of concern.
One, is the "internal" folder structure /home/user/public_html/site1/site2/site3
The other is what visitors see: web facing folder...
Based on how things are "working".. Currently othersite is in a subfolder of zencartsite, but it can also be reached directly by
othersite . com. What happens after that is all on how the software works at othersite . com
Now I didn't add in/offer any of the other "suggestions" that previously existed or were commented out, because 1) they were commented out
and 2) they may not have been transferred (old .htaccess 1 included some protections of not copying images... May want to have those
added in/back or something similar that doesn't require so much effort to maintain)...
Anyways, the above will provide rewriting for zencartsite and be disabled for othersite. If you need othersite to also use the rewriter
because it too has gone zen, then would need to do some other things to make it work, but I believe the above will put you back in biz.