I also tried jquery 2 and the option to load in the footer
There’s an error message in the console which suggests that one of your other scripts is calling a non-existent file from the site and getting an HTML page instead.
Uncaught SyntaxError: Unexpected token <
The unexpected token is the < in <!DOCTYPE html> (i.e. an HTML page), which should not be appearing in a JavaScript.
The breakage is stopping all JavaScript before Rotating Tweets gets to start rotating.
What happens if you switch off the other plug-ins one at a time to try and identify which one it is?
Martin
First of all thank you for your answer. I have updated wordpress to 4.1 and I have disabled all plugins. again I turned on the classic theme of wordpress
I renamed the folder containing the script and it works now ! many thanks for this great plugin.