Unable to perform call transfer & call park through SIP Trunk (SKYPE)

[lingchiawee]

The Scenario is:

I have set up a SIP trunk to SKYPE and we are able to make outbound call to a number via SIP Trunk.
After the call is established, when we tried to make call transfer, the call DROP and the phone at the other end shows error "Temp Fail".

I tried to "enable MTP" in SIP Trunk and We are able to perform call-transfer but it limits the call session to 1.

Anyone has facing the same issue?

[Naser Khan]

I do also have same\similar issue from our CUCM SIP trunk to 3rd party server transfer doesn't work. Once we enable MTP then it will work. Other calls if we call directly it is working.

[Manish Gogna]

MTP is needed to invoke supplementary functions like hold, transfer etc. Make sure that the MTP is checked on SIP trunk, MTP is assigned to the MRGL of the device pool on SIP trunk and has sufficient resources.

HTH

Manish