How to solve Skype for Business and Spectralink IP-DECT call transfer issue

Hi All,

here you can find how to solve the problem if you encounter call transfer issues in a scenario with a Spectralink IP-DECT Server 200-400-6500 integrated as a Trusted App in Skype for Business On-Prem.
We have seen this behaviour after upgrading firmware to 18Ba version.
Many thanks to my collegue Paolo Centenaro for doing these tests first.

First of all make sure to have a Full System Backup

Open a second browser tab to this URL https://<SpectralinkServerIP>/config/list
you will find a page like this one

Hit F3 to search in the page for sip.send

to solve the issue you have to change sip.send_bye_with_referfrom true to false, 
to do that you have to change the URL from /config/list to /config/set

in Variable insert sip.send_bye_with_refer and in Value inser false, than click Set.
Check the /config/list page, now you will see this configuration

Make some test calls, now the transfer should works correctly.
Hope this could help some of you.
Best Regards

Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Blog at

Up ↑

%d bloggers like this: