I've reviewed your install and the reason for the blank pages on profile while GJ tab is enabled is partially due to the following which is seen with debug mode enabled and maximum error reporting within Joomla global configuration.

This happens at the below line.

I've disabled the plugin "MyBlog Tab" in CB > Plugin Management to resolve the above error.

After further review it seams to be a memory related issue as no further error display is provided on blank pages and occasionally an internal error is kicked out. Please review your server error logs or PM access to server panel (cPanel, etc..). If you're using PHP.ini to improve memory limits please ensure it's in your Joomla root and root/administrator.

For the time being I've disabled the GJ tab, which resolves the issue but of course removes the tab from profiles.

O right its a conflict between myblog tab and groups tab ? or something like that

No, it's a bug in the MyBlog plugin. It's checking for a comment extension in its database queries that does not exist. I'm guessing their plugin is not considering the configuration of the component which is set not to check for comments. You may want to relay the findings to the MyBlogs developer.

Ok I,ll pm you

Appreciated, will continue review.

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