How do I set the date and time on mitel superset 4015?

You bought the wrong phone Lindsay. This is a system phone and only talks to the System Control Network Box. It won't work as a standalone phone. The system box is the equivalent of a company switchboard operator.

Mitel Superset 4015 Phone

Office Phone Shop https://www.officephoneshop.com > ... > Mitel
The Mitel Superset 4015 is a multi line digital telephone that is compatible with the Mitel Networks SX2000 system, Mitel LIGHTWARE 29 or higher.

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http://www.telecomuserguides.com/manuals/filesupload/changetime/Mitel.htm

The time and date are programmed through system programming. A 4015 phone cannot do this programming. A 4150 phone setup as a subattendant phone with the "attendant setup time/date" class of service option enabled for the 4150's class of service can change the system time and date. This is accessed through the LCD touch screen keys of the 4150. Scroll through the options in the screen until you find set time /date.
Also an attendant console with the "attendant setup time/date" class of service option enabled for its class of service can change the time and date. Press the function button then choose attendant function.
Choose set time. Enter the time in four digits as in 0800 for 8:00. Choose PM if needed. Choose set.
Choose exit to finish.

No. The Mitel Superset 4015 is a proprietary digital phone that will only work on Mitel telephone systems. It will not work on some of the older analog Mitel systems.

Press the Messages button without lifting the handset. Read the display and follow the buttons.

This will have to be set by your System administrator or by your vendor by logging into the phone system.

Hi,
Here's a link to a user's manual for your phone.

http://www.comm-links.co.uk/download/Mitel%20Superset%204015%20User%20Guide.pdf

Page 26 discusses message handling.
I hope this helps you. Good luck!

Read the manual that comes with your Mitel superset 4Dn. if you dont find the solution let me know.

repeat the connection and the unlocked no if you have it better use it

Sorry to tell you, but the Superset 4015 is not capable of doing this conference feature.

It has loud speaker capabililties (for paging, or listening to calls), but no microphone for your conference meeting.