After configuring Unified Logon for Web Console following:
And setting permissions for specific users, Unified Logon doesn't work.
When the user logged on the OS (which should be the same specified on "Security Profiles") opens WAC, the following error is shown:
"Unified Logon failed. Either the logged in user is not a valid DSM user pr unified login is not configured properly"
After this, if the credentials are entered manually, the login works (for WINNT and LDAP).
Client Automation - All Versions
This could be caused by a wrong configuration of IIS, all settings for Windows Authentication must be set to "Disabled", as shown here (with wrong values):