The other day i was getting this error:

Warning: mysql_query(): supplied argument is not a valid MySQL-Link resource in /var/www/web/forums/page.php on line 429

I tried to find out what the problem was. After researching how i can fix this error, i found the answer.

The problem was that i had given the the wrong username and database name when mysql script tried to connect to the database.

So basically this error means that your script cannot connect to the database. You have to make sure you don't have any typos and all the login information is correct like hostname, username, password, database name.

Hope this helps

Courtesy: Support