Page Unresponsive while Importing in SEN

When I try to import standard content from another workarea (Extended), I need to choose the workarea from the list. While choosing it, Manager is not responding and showing below error.

I tried many times and I still get unresponsive message. Do I need to set any registry in my PC or change any time duration in server settings?

Note: This error occurs not while importing from workarea. But while choosing the workarea to import.