Outlook Signature won't stay set on a PC

When a users email signature when set as default for New and Reply emails but won't stay set.

Close/Exit Outlook

Open the registry (regedit)

go to the key: HKCU\Software\Microsoft\Office\16.0\Outlook\Setup

Add the key `DisableRoamingSignaturesTemporaryToggle` as a DWORD, with the value of `1`

then restart Outlook.

go to File\Options\Mail\Signatures and set the default signature to use for New and Reply emails