I can't get a database connection.

Question

Background: I've already built two sites with databases using DW CS6, PHPMySQL, and the same hosting company, so I know they allow remote connections. (I'm developing using the remote host because I've never found a tutorial for how to move it all from local XAMPP to my host - but hey, it's been working fine so far.)
I set up the database using CPanel Databases, added the user and password, no problem. Went into PHP MySQL and added a table, logged out and back in, the table is there as defined.
In DW, I double-checked the testing server, tested the connection, and it connected successfully.
Then I opened a page for editing and added a database connection (all as I had done on the previous two sites that work fine). I named the connection, entered the user, the password and tried to SELECT a database. No luck. HTTP Error 404. I manually added the database (the only one) and clicked test. Again no luck. HPPT Error 404.
I double checked the testing server, double checked the DB information, and nothing seems to work.
Any clue what I'm doing wrong? Thanks so much if you can help.

Answer 1

UPDATE:
Okay, this is really getting weird. As a typcial computer nerd, I know there are many roads to success, so if one doesn't work, try another.
Trying a different solution, I opened a test.php page and wrote the following code:
<?php
echo "<p>Now testing database connection.</p>\n";
$db_server = "localhost";
$db_username = "mcsb831_mbradmin";
$db_password = "***(redacted)***";
$link = mysql_connect($db_server, $db_username, $db_password);
if (!$link) {
    echo "Could NOT connect.<br />\n";
}else{
    echo "Connected Successfully.<br />\n";
    mysql_close($link);
I loaded the page to the server and guess what? I got the message "Connected Successfully."
Hooray! Now I know the database server is running, and the database and user name and password are valid.
I went to the DW MbrConnect01.php file (the name of the CONNECTION file that Dreamweaver creates when I tried to make the connection through DW), and verified the database name, user name, and password were correct -- I copied and pasted them from the code above to make absolutely certain there were no transcription errors. Here's that file:
<?php
# FileName="Connection_php_mysql.htm"
# Type="MYSQL"
# HTTP="true"
$hostname_MbrConnec01 = "localhost";
$database_MbrConnec01 = "mcsb831_members";
$username_MbrConnec01 = "mcsb831_mbradmin";
$password_MbrConnec01 = "***(redacted)***";
$MbrConnec01 = mysql_pconnect($hostname_MbrConnec01, $username_MbrConnec01, $password_MbrConnec01) or trigger_error(mysql_error(),E_USER_ERROR);
?>
And guess what?
I GOT THE STINKING ERROR MESSAGE AGAIN!!
(See previous post for the full text of the message.
Yes, I checked the server using an FTP browser for the presence of the required files, and they are there.
Does anyone have a clue what's going on here? I would absolutely love to use DW's DB automation tools, but none of them will work if I can't get a DW connection to work.
I notice that my code uses mysql_connect while the DW-generated code uses mysql_pconnect (which is deprecated), could that be the culprit? How do I fix it if so?
PLEASE, can someone help?