Yealink SIP-T54S Administrator's Manual page 319

For each soft key that you want to disabled, just move the string in the enabled soft key list to
disabled soft key list.
Save the change and place this file to the provisioning server.
3.
Specify the access URL of the softkey layout template in the configuration files.
4.
Procedure
Specify the access URL of the softkey layout template using the configuration files.
Central Provisioning
(Configuration File)
Details of Configuration Parameters:
Parameters
custom_softkey_call_failed.url
Description:
<y0000000000xx>.cfg
Configuring Basic Features
Specify the access URL of the
softkey layout template.
Parameters:
custom_softkey_call_failed.url
custom_softkey_call_in.url
custom_softkey_connecting.url
custom_softkey_dialing.url
custom_softkey_ring_back.url
custom_softkey_talking.url
Permitted Values
URL within 511 characters
Default
Blank
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