Help please. I'm new with joomla and I'm getting the error below. Help please?

( ! ) Notice: Undefined index: data in C:\wamp\www\ps69\modules\mod_xcalendar\helper.php on line 20
Call Stack
#	Time	Memory	Function	Location
1	0.0013	384352	{main}( )	..\index.php:0
2	0.1832	8254744	JSite->render( )	..\index.php:49
3	0.1978	8610784	JDocumentHTML->render( )	..\application.php:262
4	0.1978	8610784	JDocumentHTML->_renderTemplate( )	..\html.php:322
5	0.2057	8696720	JDocumentHTML->getBuffer( )	..\html.php:502
6	0.2057	8697088	JDocumentRendererModules->render( )	..\html.php:276
7	0.2826	10194024	JDocumentRendererModule->render( )	..\modules.php:33
8	0.2827	10194472	JModuleHelper::renderModule( )	..\module.php:95
9	0.2856	10246376	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\mod_xcalendar.php' )	..\helper.php:162
10	0.2866	10298848	modXcalendarHelper::getCalendario( )	..\mod_xcalendar.php:17

( ! ) Notice: Undefined index: data in C:\wamp\www\ps69\modules\mod_xcalendar\helper.php on line 51
Call Stack
#	Time	Memory	Function	Location
1	0.0013	384352	{main}( )	..\index.php:0
2	0.1832	8254744	JSite->render( )	..\index.php:49
3	0.1978	8610784	JDocumentHTML->render( )	..\application.php:262
4	0.1978	8610784	JDocumentHTML->_renderTemplate( )	..\html.php:322
5	0.2057	8696720	JDocumentHTML->getBuffer( )	..\html.php:502
6	0.2057	8697088	JDocumentRendererModules->render( )	..\html.php:276
7	0.2826	10194024	JDocumentRendererModule->render( )	..\modules.php:33
8	0.2827	10194472	JModuleHelper::renderModule( )	..\module.php:95
9	0.2856	10246376	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\mod_xcalendar.php' )	..\helper.php:162
10	0.2888	10312328	modXcalendarHelper::getMese( )	..\mod_xcalendar.php:19

( ! ) Notice: Undefined index: data in C:\wamp\www\ps69\modules\mod_xcalendar\helper.php on line 72
Call Stack
#	Time	Memory	Function	Location
1	0.0013	384352	{main}( )	..\index.php:0
2	0.1832	8254744	JSite->render( )	..\index.php:49
3	0.1978	8610784	JDocumentHTML->render( )	..\application.php:262
4	0.1978	8610784	JDocumentHTML->_renderTemplate( )	..\html.php:322
5	0.2057	8696720	JDocumentHTML->getBuffer( )	..\html.php:502
6	0.2057	8697088	JDocumentRendererModules->render( )	..\html.php:276
7	0.2826	10194024	JDocumentRendererModule->render( )	..\modules.php:33
8	0.2827	10194472	JModuleHelper::renderModule( )	..\module.php:95
9	0.2856	10246376	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\mod_xcalendar.php' )	..\helper.php:162
10	0.2893	10312840	modXcalendarHelper::getNav( )	..\mod_xcalendar.php:20

( ! ) Notice: Undefined variable: id in C:\wamp\www\ps69\modules\mod_xcalendar\helper.php on line 201
Call Stack
#	Time	Memory	Function	Location
1	0.0013	384352	{main}( )	..\index.php:0
2	0.1832	8254744	JSite->render( )	..\index.php:49
3	0.1978	8610784	JDocumentHTML->render( )	..\application.php:262
4	0.1978	8610784	JDocumentHTML->_renderTemplate( )	..\html.php:322
5	0.2057	8696720	JDocumentHTML->getBuffer( )	..\html.php:502
6	0.2057	8697088	JDocumentRendererModules->render( )	..\html.php:276
7	0.2826	10194024	JDocumentRendererModule->render( )	..\modules.php:33
8	0.2827	10194472	JModuleHelper::renderModule( )	..\module.php:95
9	0.2856	10246376	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\mod_xcalendar.php' )	..\helper.php:162
10	0.2896	10313392	modXcalendarHelper::getMenuid( )	..\mod_xcalendar.php:21

( ! ) Notice: Undefined index: data in C:\wamp\www\ps69\modules\mod_xcalendar\tmpl\default.php on line 17
Call Stack
#	Time	Memory	Function	Location
1	0.0013	384352	{main}( )	..\index.php:0
2	0.1832	8254744	JSite->render( )	..\index.php:49
3	0.1978	8610784	JDocumentHTML->render( )	..\application.php:262
4	0.1978	8610784	JDocumentHTML->_renderTemplate( )	..\html.php:322
5	0.2057	8696720	JDocumentHTML->getBuffer( )	..\html.php:502
6	0.2057	8697088	JDocumentRendererModules->render( )	..\html.php:276
7	0.2826	10194024	JDocumentRendererModule->render( )	..\modules.php:33
8	0.2827	10194472	JModuleHelper::renderModule( )	..\module.php:95
9	0.2856	10246376	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\mod_xcalendar.php' )	..\helper.php:162
10	0.2919	10342528	require( 'C:\wamp\www\ps69\modules\mod_xcalendar\tmpl\default.php' )	..\