MoFileLoader.php 500 error

We are getting a 500 error for a file within Simple Calendar for this file: https://domain.com/wp-content/plugins/google-calendar-events/vendor/symfony/translation/Loader/MoFileLoader.php

The plugin seems to be working ok, but our IT guy has concerns about this error.

I’m not at all sure it’s related, but in wp_debug logs, we are getting these two errors repeatedly:

[11-Feb-2016 03:56:35 UTC] PHP Notice:  WP_User->id was called with an argument that is <strong>deprecated</strong> since version 2.1! Use <code>WP_User->ID</code> instead. in /home3/domain/public_html/wp-includes/functions.php on line 3737
[11-Feb-2016 03:56:35 UTC] PHP Notice:  load_plugin_textdomain was called with an argument that is <strong>deprecated</strong> since version 2.7 with no alternative available. in /home3/domain/public_html/wp-includes/functions.php on line 3739

Can you let me know if there is something we sould be doing about MoFileLoader.php?

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