Installing Drupal

I'm getting the following error installing drupal 7 (latest version from website):

Failed to connect to your database server. The server reports the following message: SQLSTATE[HY000] [2003] Can't connect to MySQL server on 'dbserver' (13).

I am running MySQL on one windows server and httpd on another Linux server. MySQL is running just fine and on the httpd server I can connect just fine to the MySQL, as follows:

mysql -h dbserver -p --port=3001 -u drupal

Similarly I can run mysqli and pdo and it connection just fine too from my httpd server:

I have just installed Drupal onto my Yosemite box. OS X 10.10.3, and there don't seem to be any particular gotcha's, apart from the old documentation on the Drupal site referring to older versions of the OS X platform. If you are on Yosemite - ignore them if you have your own Apache installation working.
The version of Apache that comes with OSX - Yosemite is more trouble than it's worth, so I installed my own. My own MySQL and PHP as well.

Hey all,

this is getting irritating and trust me, I've searched and tried everything I have found to solve this problem but no luck so far.

The problem is that when I try to install Drupal 7.37 on a remote server (which I have no control of), I get an internal server error. I have moved Drupal to the server via FTP, like so many times before, but when I go to the url the error comes up.

Need a quick solution for migration to Drupal

IIS 7.5
MySql 5.6
Drupal 7.37

I have created the database without incident. Am able to validate PHP is working with IIS. I go run install.php and receive the following from IIS

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.

I have followed ALL the installation instructions several times but still get "juicebox library could not be detected". Despite downloading juicebox lite 5 times I never get the files mentioned, eg juicebox.js or /classic/themes.css. My wife's art exhibition opens tomorrow. Can anyone help?