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How to enable cookies

Microsoft Internet Explorer 6, 7: 
Menu [Tools] -> [Internet Options] -> [Privacy]: set the slider bar to "Medium" (affect all internet sites), or click on "Sites" and add "www.npss-confs.org" to the ALLOWED list.

Mozilla FireFox:
Menu [Tools] -> [Options] -> [Privacy]: check the box "Accept cookies from sites", or click on "Exceptions" and add "www.npss-confs.org" to the ALLOWED list.