[TYPO3] Extended Calendar error

[WindTech]

I have installed the extended calendar module and included the plugin on 
a page.  When I view that page I get the following php error message:

Warning: Invalid argument supplied for foreach() in 
/typo3/typo3conf/ext/calendar/pi1/class.tx_calendar_pi1.php on line 721

Warning: Cannot modify header information - headers already sent by 
(output started at 
/typo3/typo3conf/ext/calendar/pi1/class.tx_calendar_pi1.php:721) in 
/typo3/typo3_src-3.8.0/typo3/sysext/cms/tslib/class.tslib_fe.php on line 
2612

Here is the relevant php code

		/*
		 * First we load all the objects that are now our own.
		 * We use the functions that are defined in $conf['injectObjects.'] 
from the TS config.
		 * If of those points to a userfunction, which we will call.
		 */
		foreach ($this->conf['injectObjects.'] as $o) {
			/* We need to give the userfunction the the range as an argument.  */
			$range = array ("fromYear" => $fromYear, "fromMonth" => $fromMonth, 
"fromDay" => $fromDay, "toYear" => $toYear, "toMonth" => $toMonth, 
"toDay" => $toDay,);
			/* Now call it.  Notice the $o, it's the Typoscript config.  That way 
you can configure your user function */
			$theEvents = $this->cObj->callUserFunction($o['getObjectsInRange'], 
$o, $range);