Enabling Lync Web App Access for Anonymous Users

For anonymous users (users not enabled for Lync) to join meetings through Lync Web App, you must configure the web service configuration for your Lync topology to allow this. This is done using the Set-CSWebServiceConfiguration PowerShell cmdlet. An example of how to perform this configuration is shown here:

1. Open the Lync Server Management Shell.

2. Run the following command to see the existing web service configuration:

Get-CSWebServiceConfiguration

Here is the sample output:

Click here to view code image

Identity                             : Global
TrustedCACerts                       : {}
MaxGroupSizeToExpand                 : 100
EnableGroupExpansion                 : True
UseWindowsAuth                       : Negotiate
UseCertificateAuth                   : True
UsePinAuth                           : True
AllowAnonymousAccessToLWAConference  : False
EnableCertChainDownload              : True
InferCertChainFromSSL                : True
CASigningKeyLength                   : 2048
MaxCSRKeySize                        : 16384
MinCSRKeySize                        : 1024
MaxValidityPeriodHours               : 8760
MinValidityPeriodHours               : 8
DefaultValidityPeriodHours           : 4320
MACResolverUrl                       :
SecondaryLocationSourceUrl           :
ShowJoinUsingLegacyClientLink        : True
ShowDownloadCommunicatorAttendeeLink : True
AutoLaunchLyncWebAccess              : True
ShowAlternateJoinOptionsExpanded     : False
UseWsFedPassiveAuth                  : False
WsFedPassiveMetadataUri              :
AllowExternalAuthentication          : True

By default, there is only a Global web service configuration. However, if you have previously configured site- or pool-specific configurations, you can access them through the following command:

Get-CSWebServiceConfiguration -Identity <XDS Identity>

<XDS Identity> refers to the name of the service; for a site this is site:<site name>.

3. If AllowAnonymousAccesstoLWAConference is set to false, run the following command to enable this functionality:

Set-CSWebServiceConfiguration -AllowAnonymousAccesstoLWAConference $true

4. Running Get-CSWebServiceConfiguration again should return the following results:

Click here to view code image

Identity                             : Global
TrustedCACerts                       : {}
MaxGroupSizeToExpand                 : 100
EnableGroupExpansion                 : True
UseWindowsAuth                       : Negotiate
UseCertificateAuth                   : True
UsePinAuth                           : True
AllowAnonymousAccessToLWAConference  : True
EnableCertChainDownload              : True
InferCertChainFromSSL                : True
CASigningKeyLength                   : 2048
MaxCSRKeySize                        : 16384
MinCSRKeySize                        : 1024
MaxValidityPeriodHours               : 8760
MinValidityPeriodHours               : 8
DefaultValidityPeriodHours           : 4320
MACResolverUrl                       :
SecondaryLocationSourceUrl           :
ShowJoinUsingLegacyClientLink        : True
ShowDownloadCommunicatorAttendeeLink : True
AutoLaunchLyncWebAccess              : True
ShowAlternateJoinOptionsExpanded     : False
UseWsFedPassiveAuth                  : False
WsFedPassiveMetadataUri              :
AllowExternalAuthentication          : True