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The SAMPR_USER_PREFERENCES_INFORMATION structure contains user fields.

 typedef struct _SAMPR_USER_PREFERENCES_INFORMATION {
   RPC_UNICODE_STRING UserComment;
   RPC_UNICODE_STRING Reserved1;
   unsigned short CountryCode;
   unsigned short CodePage;
 } SAMPR_USER_PREFERENCES_INFORMATION,
  *PSAMPR_USER_PREFERENCES_INFORMATION;

Reserved1: Ignored by the client and server and MUST be a zero-length string when sent and returned.

For information on all other fields, see section 2.2.6.1.