After installing a Service Desk patch and running pdm_configure to complete the install, it is possible that pass-through authentication stops working, i.e. users are prompted for a username and password where in the past they were not.
Pdm_configure has been known to cause "Enable anonymous access" setting in IIS to be checked. Refer to KB document TEC407411. If you discover that after running pdm_configure, users are presented with a username/password prompt, you should examine IIS settings, in particular, follow these steps from TEC407411:
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