---
title: Lync / Skype for Business – Trouble to search external Skype contacts - cubesys
description: NOTE this does not apply if you are full Skype for Business OnlineAs Microsoft is hardening his platforms, you may (or your end-users) have issue with Lync or Skype for Business on-premises deployment looking up for external contact (aka public federation and/or Skype consumer directories), as shown in the below…
---

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# [Lync / Skype for Business – Trouble to search external Skype contacts - cubesys](https://www.cubesys.com.au/blog/lync-skype-for-business-trouble-to-search-external-skype-contacts)

 Written by [cubesys](https://www.cubesys.com.au/blog/author/cubesys) | Jan 13, 2020 1:00:00 PM

**NOTE** this does not apply if you are **full Skype for Business Online**

As Microsoft is hardening his platforms, you may (or your end-users) have issue with Lync or Skype for Business **on-premises** deployment looking up for external contact (aka public federation and/or Skype **consumer** directories), as shown in the below screenshot.

<https://www.cubesys.com.au/hubfs/Imported_Blog_Media/image_thumb-99.png>

This is a known issue and easy to fix.

This just means you did not have implemented (or incorrectly implemented) support for **TLS 1.2**

If you lookup your Lync/Skype for Business front-end server you will probably find an error with the event ID Event ID 62044.

<https://www.cubesys.com.au/hubfs/Imported_Blog_Media/image_thumb1-81.png>

To fix this issue, you need to follow the documentation to enable TLS 1.2 on your **Edge** servers ([https://docs.microsoft.com/en-us/skypeforbusiness/manage/topology/disable-tls-1.0-1.1](https://docs.microsoft.com/en-us/skypeforbusiness/manage/topology/disable-tls-1.0-1.1)). As this is a quite long documentation, the most important thing to enable TLS 1.2 support is as below but please read the documentation anyway .

You need to create/update the following registry keys (you can save the below as a REG file), once the registry keys have been updated, restart your Edge server:

> Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINESOFTWAREMicrosoft.NETFrameworkv2.0.50727] “SchUseStrongCrypto”=dword:00000001 [HKEY_LOCAL_MACHINESOFTWAREMicrosoft.NETFrameworkv4.0.30319] “SchUseStrongCrypto”=dword:00000001 [HKEY_LOCAL_MACHINESOFTWAREWow6432NodeMicrosoft.NETFrameworkv2.0.50727] “SchUseStrongCrypto”=dword:00000001 [HKEY_LOCAL_MACHINESOFTWAREWow6432NodeMicrosoft.NETFrameworkv4.0.30319] “SchUseStrongCrypto”=dword:00000001 [HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionInternet SettingsWinHttp] “DefaultSecureProtocols”=dword:00000AA0 [HKEY_LOCAL_MACHINESOFTWAREWow6432NodeMicrosoftWindowsCurrentVersionInternet SettingsWinHttp] “DefaultSecureProtocols”=dword:00000AA0 [HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSecurityProvidersSCHANNELProtocolsTLS 1.2] [HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSecurityProvidersSCHANNELProtocolsTLS 1.2Client] “DisabledByDefault”=dword:00000000 “Enabled”=dword:00000001 [HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSecurityProvidersSCHANNELProtocolsTLS 1.2Server] “DisabledByDefault”=dword:00000000 “Enabled”=dword:00000001

[View full post](https://www.cubesys.com.au/blog/lync-skype-for-business-trouble-to-search-external-skype-contacts)

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