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Got the following error during the plugin activation
The plugin generated 1 character of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.
here is the code of that plugin http://pastebin.com/ZKrKQbPv
Also i can't able to edit plugin content via wordpress plugin editor. When i click save it shows “headers already sent” error.
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make sure BOTH one.php and two.php contain ONLY the following code if keeping blank:
<?php
Place that at the very top of the files and save and upload them to server. By including them as they are blank they have a newline in them which is being output. This will fix it. DO NOT put a closing ?> tag. It's recommended you don't end your files with them since it increases the likelihood as well of putting newlines by accident.