broovers

You can probably open your database by entering the site url and add /phpmyadmin
example: https://www.google.nl/phpmyadmin

You open your database there and look at the following tables:
wp_events_rec
wp_ec3_schedule

These are created by the plugin itself. The next problem is one im running in to as well, the plugin writes some entries in the next table, but i cant seem to find all the entries:
wp_options

one way of looking for the entries is by searching for an entry that contains the following text: schedule

I hope it helps you out a bit.

It sounds to me that the function was Depricated. This happend to me as well when i started running it on Linux.

I had another MySql version running which meant the function it appeals to to get data out of the database wasn’t supported in this SQL version.

it is also a reason why users get the No valid XML error.