This tutorial works for jDownloads 1.9.0 version for Joomla 2.5.x and Joomla 3.x
To remove copyright footer message, open the folder components/com_jdownloads and edit the file jdownloads.php
Find (use ctrl+F) and remove the following lines of code:
$footer .= '<div style="text-align:center" class="jd_footer"><a href="http://www.jDownloads.com" target="_blank" title="www.jDownloads.com">'.$power.'</a></div>';
For New jDownloads Version 3.2.x and Joomla 3.x.x,
To remove copyright footer message, you need to edit multiple files.
Open the folder components/com_jdownloads/views/categories/tmpl/ and edit the file default.php
Find (Use ctrl+F) the following lines of code (towards the very end of page):
$footer .= JDHelper::checkCom();
Comment it like this:
// $footer .= JDHelper::checkCom();
Repeat the steps for every default.php file in tmpl folder. For example, open components/com_jdownloads/views/category/tmpl/ and edit default.php in the same way as explained above.
For New jDownloads Version 3.2.x and Joomla 3.x.x, Simpler Method
To remove copyright footer message, in this method, you need to edit only one file.
Open the folder components/com_jdownloads/helpers/ and edit the file jdownloadshelper.php
Find (Use ctrl+F) the following lines of code:
if (strrev($jlistConfig['com']) ... ';}
Comment it like this:
/*** if (strrev($jlistConfig['com']) ... ';} **/
Hope it works!