This problem might be connected to your browser or some web-security software on your end.
each for both http and https, in your browser and any firewall software, browser privacy add-on, etc. that you may be running on your computer.
Our website supports all major modern browsers, but for the best experience, we recommend using the latest version of Firefox, Chrome or Safari.
Please update Adobe Flash as well (version 11.1 or above is necessary)
*Note: If you are experiencing this issue from a protected network, you may need to ask the responsible IT person to make these adjustments for you. This is common if you are trying to access Prezi.com from an educational institution or a company network.
For more information please see these articles in our Knowledge Base:
General advice on firewalls and security settings relating to Prezi
System requirements for Prezi