I have tried some solutions like adding ini_set('display_errors', 1); in my index.php file in the root and even in the /downloader folder but nothing happen. I even checked for the permissions for the folders required, and they are having 0755 as permissions. But still there is no error/warning. My site is working well and there isn't any issue in the admin panel. I have to add some extensions. Any help is very much appreciated.
Did you try with error_reporting(E_ALL); in index.php file?
Try to view page source it may also be helpful. One alternate that you can use that if the extension is free try downloading from http://www.freegento.com/ddl-magento-extension.php site by providing extension key.
I tried doing by this even error_reporting(E_ALL | E_STRICT); in index.php, shows nothing.
And in the view page source, there is just <html><body></body></html> tags and nothing else.
And the link yopu provided, by that it means i have to convert the extension into package and then have to install folder by folder right..
Any other alternative solution is much appreciated @muk_t ...