Earlier versions of Sitecore did not support the defaultProfileItemID attribute in domains.config. The setting S4S.DefaultProfile in the S4S.config can be used as an alternative if required. It should be set to the same value as would otherwise be used for the defaultProfileItemID.

<!--
The S4S.DefaultProfile setting provides backwards compatibility for older versions of Sitecore (Sitecore CMS 6.0.1 Rev. 090317)
where the defaultProfileItemID property isn’t available on the domain in Domains.config.
When required, this should be the GUID for /sitecore/system/Settings/Security/Profiles/SalesforceContact (only appears in the CORE database)
-->
<setting name="S4S.DefaultProfile" value="{EEBD0790-4AE5-459A-B579-93F701AD30E1}" />

Next Step

Configuring ASP.NET Security Providers (Pre-Sitecore 9)

Steps

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