To change your day greeting on a Samsung iDCS 28D, iDCS 18D, DS-5021 and DS-5014 telephone:

Press the voicemail button
Press * # 0000
Enter the system password
Press 1 to edit system prompts
Enter 1001 for the Day prompt
Press 1 to listen to the current prompt.  If this is not the prompt you want to record press * *
If this is [...]