Page it gives me error messages.

Admin

Hi,
I have installed a plugin imbaChat in my wordpress site. After that whenever I click on EDIT of any post or page it gives me error messages.
I have tried with basic themes and also a deactivated plugin but it's not working.
Can you please let me know how I can i fix this?

Admin

You need to update the plugin to version 3.0.9 it will remove the first deprecated.
the rest of the notice is probably caused by an old version of wordpress preferably to update to the latest (what version of wordpress do you have installed?)
or
Switch your site from debug mode to run mode, this can be done in the file wp-config.php, which is in the root of the site and find the line define( 'WP_DEBUG ', true ); instead write in define( 'WP_DEBUG ', false ); this will remove all unnecessary notice.