When I go to Download new plasme widgets (Panel - Add widgets - Get New Widgets), it only shows the wait cursor without showing any entries. My internet connection is working fine - I am writing this post

I am also unable to use the weather forecast in system tray and the flickr plasmoid. The problem is the same - they are not able to access the net, I guess. In the weather forecast, when I enter city to search, nothing happens. The wait indicator keeps moving. Similarly, when I try to authenticate flickr, browser window does not open. So I cant authenticate.

Does your system need to use a proxy to connect to the internet? If so, and you don't use Konqueror, KDE may not be configured to use the proxy, preventing it from working. Head to System Settings > Network Settings > Proxy to configure KDE to use your proxy.

No. I dont use a proxy.

But it was mysteriously solved when I restarted. Could access all the stuff.

Thanks for your help.