Solved it!!!!!!!!! 
If anyone else is having the same problem:
Open includes/functions/sessions.php (NOT in the admin folder)
Copy this code (found it here on the forum)
PHP Code:
if(!version_compare(phpversion(),"4.3.3",">=")){
setcookie(
session_name(),
session_id(),
ini_get("session.cookie_lifetime"),
"/"
);
}
Search for "session_regenerate_id();". Paste the code right after that. First it did'nt work, but in the file there are 4 lines of code with "session_regenerate_id();"
Paste the code after every session_regenerate_id();.
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