Based on the advice of Iguinn and MuS, I went into the Splunk Folder using MAC's "Finder". Going into Apps/Splunk/, I went folder by folder to find the passwd document (located in /Splunk/etc). Then, I set up a folder called OLD and moved the PASSWD document into it.
At first, it appeared that this did not solve the problem, and then I realized it was necessary to restart.
I simply used the admin and changeme entries and was able to proceed.
Thanks so much for taking the time to help a beginner. I speaks well of the Splunk User Community,
To reset the Splunk password, go to the directory and remove the passwd file.
$SPLUNK_HOME represents the directory where you installed Splunk.
cd $SPLUNK_HOME/etc mv passwd old.passwd # for mac or linux
Then restart Splunk. The Splunk user will be "admin" and the password will be "changeme".