<div class="content"><p> </p><p>The <b>FAX_EnumerateProviders (Opnum 45)</b> method is
called by the client to enumerate all the <span><a href="46aba9c4-ebb1-4b10-86ac-4bb3025657b9#gt_2ba66d72-d766-440f-b5ea-0333759b147c" data-linktype="relative-path">FSPs</a></span> installed on
the server. </p><p>The server MUST validate that the client&#39;s fax user account
has access to enumerate providers. The <i>Buffer</i> parameter MUST NOT be
NULL. On success, the server MUST return the FSPs installed on the fax server.</p><p>The client SHOULD free the returned buffer.</p><dl>
<dd>
<div><pre> error_status_t FAX_EnumerateProviders(
   [in] handle_t hFaxHandle,
   [out, size_is(, *BufferSize)] LPBYTE* Buffer,
   [out, ref] LPDWORD BufferSize,
   [out, ref] LPDWORD lpdwNumProviders
 );
</pre></div>
</dd></dl><p><b>hFaxHandle: </b>The RPC binding handle for this
call. The client SHOULD reuse the RPC binding handle used as an input <i>hBinding</i>
argument for the <b>FAX_ConnectFaxServer</b> (section <span><a href="5cbfd38d-7a14-4560-ad24-9ed78f19a3bb" data-linktype="relative-path">3.1.4.1.10</a></span>) or <b>FAX_ConnectionRefCount</b>
(section <span><a href="a92941ac-bd07-4a71-af85-c2c157c97cf9" data-linktype="relative-path">3.1.4.1.11</a></span>) method
call used to connect to the fax server.</p><p><b>Buffer: </b>A pointer to the address of a buffer
to receive an array of <b>FAX_DEVICE_PROVIDER_INFO</b> (section <span><a href="7abbf16c-90bb-4bf6-83ec-e0068c7cbc36" data-linktype="relative-path">2.2.30</a></span>)
structures. Each structure contains information about one fax device provider,
as it pertains to the entire fax service.</p><p><b>BufferSize: </b>A pointer to a <b>DWORD</b> (<span><a href="../ms-dtyp/cca27429-5689-4a16-b2b4-9325d93e4ba2" data-linktype="relative-path">[MS-DTYP]</a></span>
section <span><a href="../ms-dtyp/262627d8-3418-4627-9218-4ffe110850b2" data-linktype="relative-path">2.2.9</a></span>)
in which to return the size, in bytes, of the buffer.</p><p><b>lpdwNumProviders: </b>A pointer to a <b>DWORD</b>
variable to receive the number of <b>FAX_DEVICE_PROVIDER_INFO</b> that the
method returns in <i>Buffer</i>. This number MUST be equal to the total number
of FSPs installed on the target server.</p><p><b>Return Values: </b>This method MUST return
0x00000000 (ERROR_SUCCESS) for success; otherwise, it MUST return one of the
following error codes, one of the fax-specific errors that are defined in
section <span><a href="cbe6c4fb-4dda-4f6c-9701-0d490ba0d105" data-linktype="relative-path">2.2.52</a></span>, or one of
the other standard errors defined in <span><a href="../ms-erref/1bc92ddf-b79e-413c-bbaa-99a5281a6c90" data-linktype="relative-path">[MS-ERREF]</a></span>
section <span><a href="../ms-erref/18d8fbe8-a967-4f1c-ae50-99ca8e491d2d" data-linktype="relative-path">2.2</a></span>.</p><dl>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Return value/code</p>
   </th>
   <th>
   <p>Description</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>
  <p>ERROR_ACCESS_DENIED</p>
  <p>0x00000005</p>
  </td>
  <td>
  <p>Access is denied. The client&#39;s fax user account does
  not have the <b>FAX_ACCESS_QUERY_CONFIG</b> access rights required for this
  operation.</p>
  </td>
 </tr><tr>
  <td>
  <p>ERROR_INVALID_PARAMETER</p>
  <p>0x00000057</p>
  </td>
  <td>
  <p>The parameter is incorrect. This error is returned if
  the <i>BufferSize</i> and/or the <i>lpdwNumProviders</i> parameters are set
  to NULL pointer values.</p>
  </td>
 </tr><tr>
  <td>
  <p>ERROR_INTERNAL_ERROR</p>
  <p>0x0000054F</p>
  </td>
  <td>
  <p>The fax server failed to custom marshal the array of <b>FAX_DEVICE_PROVIDER_INFO</b>
  structures to be returned to the client.</p>
  </td>
 </tr><tr>
  <td>
  <p>FAX_ERR_SRV_OUTOFMEMORY</p>
  <p>0x00001B59</p>
  </td>
  <td>
  <p>The fax server failed to allocate sufficient memory
  for the return buffer to hold the <b>FAX_DEVICE_PROVIDER_INFO</b> to be
  returned to the client.</p>
  </td>
 </tr></tbody></table>
</dd></dl><p><b>Exceptions Thrown: </b>No exceptions are thrown
except those that are thrown by the underlying <span><a href="46aba9c4-ebb1-4b10-86ac-4bb3025657b9#gt_8a7f6700-8311-45bc-af10-82e10accd331" data-linktype="relative-path">RPC</a></span> protocol, <span><a href="../ms-rpce/290c38b1-92fe-4229-91e6-4fc376610c15" data-linktype="relative-path">[MS-RPCE]</a></span>.</p></div>