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VVX 401 Skype For Business PIN Authentication

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VVX 401 Skype For Business PIN Authentication

  •  UC version
  • VVX 401
  • Skype For Business Server 2015


I'm trying to get some newly purchased VVX401's to work with our existing setup where we have CX500 and CX600's signing in using PIN Authentication without issue.

Each time I'm met with 'Skype for Business authentication failed. Sign in again.'


The phones have latest supported UC version for Skype.

Base profile set to Skype.

All the DHCP options are as before to support PIN authentication.

Corrent time is shown.

Logs show the certificate being downloaded from the Skype server OK.

PIN sign-in works for a normal user using the dial-in conf set PIN.

CAP mode is on.


Any pointers will be appreciated.








Message 1 of 2
Polycom Employee & Community Manager

Re: VVX 401 Skype For Business PIN Authentication

Hello @timbrooke ,


welcome to the Poly Community.

Please ensure you always check the FAQ's and/or utilize the community search before posting any new topics or follow up posts.

Jan 17, 2017 Question:How can I troubleshoot simple Skype for Business, LYNC or Office365 issues?

Resolution: Have a look => here <=


Jul 11, 2014 Question: Why can we not sign in to Skype for Business via Pin & Extension?

Resolution: Please verify that the phone has the => correct time <= and the Option 43 and Option 120 is setup in the DHCP scope as explained =>here <= or => here <= 

Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.

Best Regards

Steffen Baier

The title Polycom Employee & Community Manager is a community setting and does not reflect my role. I am just a simple volunteer in the community like everybody else. All posts and words are my own & do not represent the views of Employer.


Notice: This community forum is not an official Poly support resource, thus responses from Poly employees, partners, and customers alike are best-effort in attempts to share learned knowledge. If you need immediate and/or official assistance please open a service ticket through your proper support channels.
Please also ensure you always check the VoIP , Video Endpoint , Skype for Business , PSTN or RPM FAQ's
Message 2 of 2