AJAX File Browser Control and User Agent Request Pool Limitations

Modern user agents can issue a limited number of concurrent requests to server. For instance IE 7 can upload and download only 2 files in parallel, or can issue 2 concurrent XmlHttpRequests. Other browsers can issue 4 concurrent requests and more. As soon as amount of concurrent downloads cannot be controlled in JavaScript the AJAX File Browser will hang if too many downloads are opened and will remain frozen until download finishes. You should not download and upload more than 1 file at a time in Internet Explorer 7, or more that 3 files in other user agents.