Editing .htaccess for an Expression Engine directory - .htaccess

Question

I am attempting to migrate a portal (including login ability) over to a new website. The new site is designed in Wordpress and all of the expression engine files are tossed into a subdirectory outside of the wordpress install.
The entire old site (which was working and all built on Expression Engine) and copy it into the sub-directory (lets call it "old".
Then I went to the .htaccess file and
Updated /old/.htaccess with the following:
RewriteBase /old/
(it was originally RewriteBase / )
It shows that it goes to the directory but it shows my index wordpress page (that is index.php BUT it is just my home page of the wordpress install and not the log in page that I expect).
This is my .htaccess file code (inside of the "old" directory which is a subdirectory of the root directory:
RewriteEngine On
RewriteBase /assets/
# Removes index.php from ExpressionEngine URLs
RewriteCond %{THE_REQUEST} ^GET.*index\.php [NC]
RewriteCond %{REQUEST_URI} !/asysteme/.* [NC]
RewriteRule (.*?)index\.php/*(.*) /$1$2 [R=301,NE,L]
# Directs all EE web requests through the site index file
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php/$1 [L]
BUt all it does is take the page to the index page of the root.

Answer 1

Check your WordPress .htaccess isn't taking control because it has to pass through that htaccess file before it gets to the subfolder htaccess file (EE). So ensure this line is in the WordPress htaccess:
RewriteCond %{REQUEST_FILENAME} !-d
Which excludes physical directories on the server from being rewritten and will let requests through to the EE folder and therefore the EE htaccess.
Your ExpressionEngine htaccess file has:
RewriteBase /assets/
Shouldn't this be:
RewriteBase /old/
Try the following:
RewriteEngine On
# Removes index.php from ExpressionEngine URLs
# RewriteCond %{THE_REQUEST} ^GET.*index\.php [NC]
# RewriteCond %{REQUEST_URI} !/asysteme/.* [NC]
# RewriteRule (.*?)old/index\.php/*(.*) /$1$2 [R=301,NE,L]
# Directs all EE web requests through the site index file
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /old/index.php/$1 [L]
To isolate the problem/solution, comment out the removal of the index.php from the URL (this is if someone has specifically entered index.php in the URL). Once the site is working, add this back in.
Remove the rewrite base to simplify things and add the sub-folder into the rewrite rule. This should then resolve the issue.