Sketch for the DS3231 not working

Here is the error that i get when i check it,
Arduino: 1.8.5 (Windows 10), Board: "Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"

DS3231_dateformat:7: error: 'RTCDateTime' does not name a type

RTCDateTime dt;

^

D:\Arduino\code\Lesson 19 Real Time Clock Module\DS3231_dateformat\DS3231_dateformat.ino: In function 'void setup()':

DS3231_dateformat:15: error: 'class DS3231' has no member named 'begin'

clock.begin();

^

DS3231_dateformat:18: error: 'class DS3231' has no member named 'setDateTime'

clock.setDateTime(DATE, TIME);

^

D:\Arduino\code\Lesson 19 Real Time Clock Module\DS3231_dateformat\DS3231_dateformat.ino: In function 'void loop()':

DS3231_dateformat:29: error: 'dt' was not declared in this scope

dt = clock.getDateTime();

^

DS3231_dateformat:29: error: 'class DS3231' has no member named 'getDateTime'

dt = clock.getDateTime();

^

DS3231_dateformat:32: error: 'class DS3231' has no member named 'dateFormat'

Serial.println(clock.dateFormat("d-m-Y H:i:s", dt));

^

DS3231_dateformat:35: error: 'class DS3231' has no member named 'dateFormat'

Serial.println(clock.dateFormat("d F Y H:i:s", dt));

^

DS3231_dateformat:38: error: 'class DS3231' has no member named 'dateFormat'

Serial.println(clock.dateFormat("jS M y, h:ia", dt));

^

DS3231_dateformat:41: error: 'class DS3231' has no member named 'dateFormat'

Serial.print(clock.dateFormat("l, z", dt));

^

DS3231_dateformat:45: error: 'class DS3231' has no member named 'dateFormat'

Serial.print(clock.dateFormat("t", dt));

^

DS3231_dateformat:49: error: 'class DS3231' has no member named 'dateFormat'

Serial.println(clock.dateFormat("U", dt));

^

exit status 1
'RTCDateTime' does not name a type

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I tried manual loading from the CD. same problem

Assume you have all necessary libraries installed properly.

Always show us your ‘current’ complete sketch.
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[code] Paste sketch here. [/code]

See this for installing libraries:

From what I can tell with the statement "#include <RTClib.h>",fatal error: RTClib.h: No such file or directory. I need a Library RTClib.h where can I get it? it is not on the CD.

Always show us your ‘current’ complete sketch.
Use CTRL T to format the sketch. Please use code tags.
Use the </> icon in the posting menu.

[code] Paste sketch here. [/code]

Google DS3231 library.

Google RTClib.h

@donmedina, do not cross-post. Other thread removed.