permalink issue

Your site is coming up, and all your menu links also come up well. Then what is the problem?

Why don’t you use a normal wordpress installation and redirect all the traffic pointing to the old HTML files.

E.g. if you want to redirect approach.html to https://www.domain.com/approach/ you can simply add the below to a .htaccess file in the root of the website:

redirect permanent / https://www.domain.com/approach/

Thank you for your reply.

Let me explain more. The original site has a flash header with navigation which point to html files, and can’t be changed. so I have to change permalink to custom structure: /%postname.html%/ and I have .htaccess like this:
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule index\.html$ https://maximpartnersllc.com [R=301,L]
RewriteRule (.+)/index\.html$ https://maximpartnersllc.com [R=301,L]
RewriteRule (.+)/(.+)\.html$ https://maximpartnersllc.com/$2 [R=301,L]
RewriteRule ^index\.php$ – [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

actually it works fine on my server, but doesn’t work when I transfer to client’s server. the difference is there are not html files on my server.

Krishna, what you saw is the original html site, not WordPress.

@frankzhang,
Sorry, I thought it is the result that you wanted to achieve.

Have a look at this link:
https://www.webconfs.com/how-to-redirect-a-webpage.php
Possibly, one of the many methods described in the article may help you. As already suggested, a 301 redirect will be the best alternative.

The final result should work like the one on my server, https://maxim.frankzhang.ca

It is very good. Also the link of the header image need to be changed. So, do you think the problem is solved now?

No, it works well on my server, but failed on client’s server, though the same setting.

Then I think, it has to do something with the client’s server settings. Are you sure that the client’s server meets the minimum requirements for WordPress hosting?