I get the following error after enabling myblog plugin on Joomla 1.7.2 with Myblog for Joomla 1.7.
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Fatal error: Call to a member function registerEvent() on a non-object in /home/xxxxx/public_html/plugins/content/compojoomcommentmyblog/compojoomcommentmyblog.php on line 24

I enabled the plugin, published the compojoommyblog mambot, and created a com_myblog component as per the guide. ( I could not find the place in /index.tmpl.html file to place the button script.) The error appears in both front end and back end and I cannot disable the plugin without getting the same error!

UPDATE: I've solved the problem. Your Myblog plugin is not compatible with Joomla 1.6/1.7. The $mainframe variable does not exist in the new Joomla, and needs to be replaced with:
$app = &JFactory::getApplication(); $app->RegisterEvent(...
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