How do I put my Mitel Superset 4015 on speaker phone during a call?

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

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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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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!

Contact your System Admin or vendor for this change.

Contact your system admin or vendor.

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

The time and date come from the Mitel Telephone system, not from the telephone set itself.

You need to access the Mitel system to make a time change.

If you can get into the system, goto the Group Administration and click on time...the rest is self explainitory.