Hello everybody,
I have the exact same problem decribe by Thirdiphoto in this post:
http://www.zen-cart.com/forum/showth...=media+manager

I create my media collection using the tools provided in ZC admin panel.
I upload the .mp3 file to the specified collection (I did specify mp3 as a Media Type before)
I assign the collection to a Music Product Item.
When I click on "add", I get redirected to my ZC admin main page.
When I go back to my media manager, the collection is visible but no product linked......


My settings:
New zen cart, latest version. 1.3.9.h
No major modifications, no templates, no add-ons.
Auto installed by simple scripts on bluehost servers

php editor: Dreamweaver cs5

After reading the solution given by Dr Byte, I opened my init_sessions.php (located in mysite\public_htlm\includes\init_includes)

On line 40, I do not have the same string of code as mentionned by Dr Byte, instead, I have:
PHP Code:
$domainPrefix = (!defined('SESSION_ADD_PERIOD_PREFIX') || SESSION_ADD_PERIOD_PREFIX == 'True') ? '.' : ''; 
I looked around but I was not able able to locate the following code in order to change it:

PHP Code:
if (strpos ( $PHP_SELF, FILENAME_PRODUCTS_PRICE_MANAGER ) === FALSE 
I looked all over the forums to try to find a solution but I was not successful.
If anyone has a clue to solve our problem, we would really appreciate the help as we are definitely noobs

I use this first post to say a big thank you to all the contributors in this forum: It was really helpful and we were able to put our website online really fast with all the good advices!!