Moved WP files and database from on host to another-asking for new install

I had to disable the database link because the WP setup option is exposed publicly when one goes to the website – it defaults right to wp-admin/install.php.
It’s clearly accessing the old database, but why is it asking to perform a new setup?
Will I overwrite the old database if I go through setup?

Have not migrated a site before. What if I disabled install.php?
TIA

Is this the guide you followed to move the site: Moving WordPress

Yes,
“If database and URL remain the same, you can move by just copying your files and database.”

So it’s not as easy as it’s supposed to be… ??
Will start with disabling install.php and then disable plugins to see if that helps.

Well, disabling the install.php just causes the return of a 404 error.
Disabling plugins through FTP does nothing.
Wordpress is clearly connecting with the old database, but its not processing any of the saved database files. It’s asking to create a new site.
Site permalinks should all be exactly the same as before since the domain has completely propagated.

I’d post a link here, but my site is completely exposed to WP install if I link database.

All database tables were checked after the move. All check out fine.

Can anyone point me to a better forum where I might post this?
TIA

The wp-config file I had before had:
$table_prefix = 'wp_';
I looked at my tables, and they were cms_ (previous coder had set up site)
I changed the config file to:
$table_prefix = 'cms_';
and get database error.

These are sample tables as viewed in phpMyAdmin:
New
cms
cms_(demo1269037527-500)_about
cms_(demo1269037527-500)_about_cms
cms_(demo1269037527-500)_accounts
cms_(demo1269037527-500)_buy_tickets
cms_(demo1269037527-500)_buy_tickets_menu
cms_(demo1269037527-500)_concerts
cms_(demo1269037527-500)_concerts_intro

Welcome to my WordPress one man discussion. ??
Hoping someone sees this and offers an idea. Any idea – I’ll take anything at this point!

Because the original working wp-config file had table prefix as wp_
can I assume that perhaps my cms_ prefix tables that were working before were somehow maybe in an enclosing table (not a programmer) labeled wp_

As mentioned before, with wp_ the database is accessed, but WordPress prompts me for a new install, which means it’s not reading all the tables currently in there.

When I changed table prefixes to cms_ ,as my tables are currently labeled, I get a database error trying to connection.

Trying to figure out what is preventing those tables from being read.

My only other option is to recreate the entire site, since it needs to be back up and running by Friday.

Any suggestion, even a stupid one, would be greatly appreciated!
I open the floor ??

Should I try overwriting all the base WP files on my site?
Still can’t troubleshoot the database error issue.

Is it possible to try and rename the table prefixes within the database to try and relink WP with the database?
Could there be some sort of directory path error preventing the database access?
Would there be a way to manually reconfigure?

When I changed table prefixes to cms_ ,as my tables are currently labeled, I get a database error trying to connection.

That means the database table prefix in wp-config.php is correct now.

But still, your database name or password or username is wrong. So check those in your Cpanel and wp-config.php.

Finally solved this issue after getting on support with my new host. They looked into my database and found that it was missing critical files for WordPress. I think what happened is that the old host gave me an old database file, even though it looked right to me.
Getting the correct file fixed everything.

BTW – songdogtech, thank you so much for responding!