diff --git a/dll/win32/shlwapi/CMakeLists.txt b/dll/win32/shlwapi/CMakeLists.txt
index 472eceb2014..6c425e78ceb 100644
--- a/dll/win32/shlwapi/CMakeLists.txt
+++ b/dll/win32/shlwapi/CMakeLists.txt
@@ -6,9 +6,13 @@ add_definitions(-D_WIN32_WINNT=0x600)
 
 add_definitions(
     -D__WINESRC__
-    -D_SHLWAPI_)
+    -D_SHLWAPI_
+    -D_ATL_NO_EXCEPTIONS)
 
-include_directories(BEFORE ${REACTOS_SOURCE_DIR}/sdk/include/reactos/wine)
+set_cpp(WITH_RUNTIME)
+include_directories(BEFORE
+    ${REACTOS_SOURCE_DIR}/sdk/include/reactos/wine
+    ${REACTOS_SOURCE_DIR}/sdk/lib/atl)
 spec2def(shlwapi.dll shlwapi.spec ADD_IMPORTLIB)
 
 list(APPEND SOURCE
@@ -28,6 +32,7 @@ list(APPEND SOURCE
     url.c)
 
 list(APPEND PCH_SKIP_SOURCE
+    autocomp.cpp
     wsprintf.c
     ${CMAKE_CURRENT_BINARY_DIR}/shlwapi_stubs.c)
 
@@ -37,7 +42,7 @@ add_library(shlwapi MODULE
     shlwapi.rc
     ${CMAKE_CURRENT_BINARY_DIR}/shlwapi.def)
 
-set_module_type(shlwapi win32dll)
+set_module_type(shlwapi win32dll UNICODE)
 target_link_libraries(shlwapi uuid wine)
 add_delay_importlibs(shlwapi userenv oleaut32 ole32 comdlg32 mpr mlang urlmon shell32 winmm version)
 add_importlibs(shlwapi user32 gdi32 advapi32 wininet msvcrt kernel32 ntdll)
diff --git a/dll/win32/shlwapi/autocomp.cpp b/dll/win32/shlwapi/autocomp.cpp
new file mode 100644
index 00000000000..bc2c3ca3f14
--- /dev/null
+++ b/dll/win32/shlwapi/autocomp.cpp
@@ -0,0 +1,226 @@
+/*
+ * PROJECT:     ReactOS shlwapi
+ * LICENSE:     LGPL-2.0-or-later (https://spdx.org/licenses/LGPL-2.0-or-later)
+ * PURPOSE:     Implement SHAutoComplete
+ * COPYRIGHT:   Copyright 2020 Katayama Hirofumi MZ (katayama.hirofumi.mz@gmail.com)
+ */
+#include <windef.h>
+#include <shlobj.h>
+#include <shlwapi.h>
+#include <browseui_undoc.h>
+#include <shlwapi_undoc.h>
+#include <shlguid_undoc.h>
+#include <atlbase.h>
+#include <atlcom.h>
+#include <wine/debug.h>
+
+WINE_DEFAULT_DEBUG_CHANNEL(shell);
+
+static HRESULT
+AutoComplete_AddMRU(CComPtr<IObjMgr> pManager, LPCWSTR pszKey)
+{
+    CComPtr<IACLCustomMRU> pMRU; // Create an MRU list
+    HRESULT hr = CoCreateInstance(CLSID_ACLCustomMRU, NULL, CLSCTX_INPROC_SERVER,
+                                  IID_IACLCustomMRU, (LPVOID *)&pMRU);
+    if (FAILED(hr))
+    {
+        ERR("CoCreateInstance(CLSID_ACLMRU) failed with 0x%08lX\n", hr);
+        return hr;
+    }
+
+    hr = pMRU->Initialize(pszKey, 'z' - 'a' + 1); // Load the list from registry
+    if (FAILED(hr))
+    {
+        ERR("pMRU->Initialize(%ls) failed with 0x%08lX\n", pszKey, hr);
+        return hr;
+    }
+
+    hr = pManager->Append(pMRU); // Add to the manager
+    if (FAILED(hr))
+        ERR("pManager->Append for '%ls' failed with 0x%08lX\n", pszKey, hr);
+    return hr;
+}
+
+static HRESULT
+IUnknown_SetOptions(CComPtr<IUnknown> punk, DWORD dwACLO)
+{
+    CComPtr<IACList2> pList;
+    HRESULT hr = punk->QueryInterface(IID_IACList2, (LPVOID *)&pList);
+    if (FAILED(hr))
+    {
+        ERR("punk->QueryInterface failed: 0x%08lX\n", hr);
+        return hr;
+    }
+
+    hr = pList->SetOptions(dwACLO);
+    if (FAILED(hr))
+        ERR("pList->SetOptions failed: 0x%08lX\n", hr);
+    return hr;
+}
+
+static CComPtr<IUnknown>
+AutoComplete_LoadList(DWORD dwSHACF, DWORD dwACLO)
+{
+    // Create a multiple list (with IEnumString interface)
+    CComPtr<IUnknown> pList;
+    HRESULT hr = CoCreateInstance(CLSID_ACLMulti, NULL, CLSCTX_INPROC_SERVER,
+                                  IID_IUnknown, (LPVOID *)&pList);
+    if (FAILED(hr)) // Failed to create the list
+    {
+        ERR("CoCreateInstance(CLSID_ACLMulti) failed with 0x%08lX\n", hr);
+        return NULL;
+    }
+
+    CComPtr<IObjMgr> pManager; // This is the manager of the multiple list
+    hr = pList->QueryInterface(IID_IObjMgr, (LPVOID *)&pManager);
+    if (FAILED(hr)) // Failed to get interface
+    {
+        ERR("pList->QueryInterface failed: 0x%08lX\n", hr);
+        return NULL;
+    }
+
+    if (dwSHACF & SHACF_URLMRU)
+    {
+        // The MRU (Most-Recently-Used) lists (with IEnumString interface)
+#define RUN_MRU_KEY L"Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\RunMRU"
+#define TYPED_URLS_KEY L"Software\\Microsoft\\Internet Explorer\\TypedURLs"
+        AutoComplete_AddMRU(pManager, RUN_MRU_KEY);
+        AutoComplete_AddMRU(pManager, TYPED_URLS_KEY);
+    }
+
+    if (dwSHACF & SHACF_URLHISTORY)
+    {
+        // The history list (with IEnumString interface)
+        CComPtr<IUnknown> pHistory;
+        hr = CoCreateInstance(CLSID_ACLHistory, NULL, CLSCTX_INPROC_SERVER,
+                              IID_IUnknown, (LPVOID *)&pHistory);
+        if (SUCCEEDED(hr))
+        {
+            pManager->Append(pHistory); // Add to the manager
+            // Set ACLO_* options
+            IUnknown_SetOptions(pHistory, dwACLO | ACLO_CURRENTDIR | ACLO_MYCOMPUTER);
+        }
+        else
+        {
+            ERR("CLSID_ACLHistory hr:%08lX\n", hr);
+        }
+    }
+
+    if (dwSHACF & (SHACF_FILESYSTEM | SHACF_FILESYS_ONLY | SHACF_FILESYS_DIRS))
+    {
+        // The filesystem list (with IEnumString interface)
+        CComPtr<IUnknown> pISF;
+        hr = CoCreateInstance(CLSID_ACListISF, NULL, CLSCTX_INPROC_SERVER,
+                              IID_IUnknown, (LPVOID *)&pISF);
+        if (SUCCEEDED(hr))
+        {
+            pManager->Append(pISF); // Add to the manager
+            // Set ACLO_* options
+            IUnknown_SetOptions(pISF, dwACLO | ACLO_CURRENTDIR | ACLO_MYCOMPUTER);
+        }
+        else
+        {
+            ERR("CLSID_ACListISF hr:%08lX\n", hr);
+        }
+    }
+
+    return pList; // The list
+}
+
+static VOID
+AutoComplete_AdaptFlags(IN HWND hwndEdit,
+                        IN OUT LPDWORD pdwSHACF,
+                        OUT LPDWORD pdwACO,
+                        OUT LPDWORD pdwACLO)
+{
+#define AUTOCOMPLETE_KEY L"Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\AutoComplete"
+    DWORD dwSHACF = *pdwSHACF, dwACO = 0, dwACLO = 0;
+    if (dwSHACF == SHACF_DEFAULT)
+        dwSHACF = SHACF_FILESYSTEM | SHACF_URLALL;
+
+    if (!(dwSHACF & SHACF_AUTOAPPEND_FORCE_OFF) &&
+        ((dwSHACF & SHACF_AUTOAPPEND_FORCE_ON) ||
+         SHRegGetBoolUSValueW(AUTOCOMPLETE_KEY, L"Append Completion", FALSE, FALSE)))
+    {
+        dwACO |= ACO_AUTOAPPEND;
+    }
+
+    if (!(dwSHACF & SHACF_AUTOSUGGEST_FORCE_OFF) &&
+        ((dwSHACF & SHACF_AUTOSUGGEST_FORCE_ON) ||
+         SHRegGetBoolUSValueW(AUTOCOMPLETE_KEY, L"AutoSuggest", FALSE, TRUE)))
+    {
+        dwACO |= ACO_AUTOSUGGEST;
+    }
+
+    if (dwSHACF & SHACF_FILESYS_DIRS)
+        dwACLO |= ACLO_FILESYSDIRS;
+    if (dwSHACF & SHACF_FILESYS_ONLY)
+        dwACLO |= ACLO_FILESYSONLY;
+
+    static BOOL s_bAlwaysUseTab = 99;
+    if (s_bAlwaysUseTab == 99)
+        s_bAlwaysUseTab = SHRegGetBoolUSValueW(AUTOCOMPLETE_KEY, L"Always Use Tab", FALSE, FALSE);
+
+    if (s_bAlwaysUseTab || (dwSHACF & SHACF_USETAB))
+        dwACO |= ACO_USETAB;
+
+    if (GetWindowLongPtrW(hwndEdit, GWL_EXSTYLE) & WS_EX_LAYOUTRTL)
+        dwACO |= ACO_RTLREADING;
+
+    *pdwACO = dwACO;
+    *pdwSHACF = dwSHACF;
+    *pdwACLO = dwACLO;
+}
+
+/*************************************************************************
+ *      SHAutoComplete  	[SHLWAPI.@]
+ *
+ * Enable auto-completion for an edit control.
+ *
+ * PARAMS
+ *  hwndEdit [I] Handle of control to enable auto-completion for
+ *  dwFlags  [I] SHACF_ flags from "shlwapi.h"
+ *
+ * RETURNS
+ *  Success: S_OK. Auto-completion is enabled for the control.
+ *  Failure: An HRESULT error code indicating the error.
+ */
+HRESULT WINAPI SHAutoComplete(HWND hwndEdit, DWORD dwFlags)
+{
+    TRACE("SHAutoComplete(%p, 0x%lX)\n", hwndEdit, dwFlags);
+
+    DWORD dwACO = 0, dwACLO = 0, dwSHACF = dwFlags;
+    AutoComplete_AdaptFlags(hwndEdit, &dwACO, &dwACLO, &dwSHACF);
+
+    // Load the list (with IEnumString interface)
+    CComPtr<IUnknown> pList = AutoComplete_LoadList(dwSHACF, dwACLO);
+    if (!pList)
+    {
+        ERR("Out of memory\n");
+        return E_OUTOFMEMORY;
+    }
+
+    // Create an auto-completion (IAutoComplete2)
+    CComPtr<IAutoComplete2> pAC2;
+    HRESULT hr = CoCreateInstance(CLSID_AutoComplete, NULL, CLSCTX_INPROC_SERVER,
+                                  IID_IAutoComplete2, (LPVOID *)&pAC2);
+    if (FAILED(hr))
+    {
+        ERR("CoCreateInstance(CLSID_AutoComplete) failed: 0x%lX\n", hr);
+        return hr;
+    }
+
+    // Keep the DLLs of CLSID_ACListISF and CLSID_AutoComplete loaded
+    hr = E_FAIL;
+    if (SHPinDllOfCLSID(CLSID_ACListISF) && SHPinDllOfCLSID(CLSID_AutoComplete))
+    {
+        // Initialize IAutoComplete2 for auto-completion
+        hr = pAC2->Init(hwndEdit, pList, NULL, NULL);
+        if (SUCCEEDED(hr))
+            pAC2->SetOptions(dwACO); // Set ACO_* flags
+        else
+            ERR("IAutoComplete2::Init failed: 0x%lX\n", hr);
+    }
+
+    return hr;
+}
diff --git a/dll/win32/shlwapi/url.c b/dll/win32/shlwapi/url.c
index c858ebde695..0ac96a03b7c 100644
--- a/dll/win32/shlwapi/url.c
+++ b/dll/win32/shlwapi/url.c
@@ -2514,6 +2514,7 @@ HRESULT WINAPI UrlCreateFromPathW(LPCWSTR pszPath, LPWSTR pszUrl, LPDWORD pcchUr
     return ret;
 }
 
+#ifndef __REACTOS__
 /*************************************************************************
  *      SHAutoComplete  	[SHLWAPI.@]
  *
@@ -2532,6 +2533,7 @@ HRESULT WINAPI SHAutoComplete(HWND hwndEdit, DWORD dwFlags)
   FIXME("stub\n");
   return S_FALSE;
 }
+#endif
 
 /*************************************************************************
  *  MLBuildResURLA	[SHLWAPI.405]
diff --git a/sdk/include/reactos/shlwapi_undoc.h b/sdk/include/reactos/shlwapi_undoc.h
index 328bd511db6..c1f92559e55 100644
--- a/sdk/include/reactos/shlwapi_undoc.h
+++ b/sdk/include/reactos/shlwapi_undoc.h
@@ -33,6 +33,7 @@ BOOL WINAPI SHAboutInfoW(LPWSTR lpszDest, DWORD dwDestLen);
 #define SHAboutInfo SHAboutInfoA
 #endif
 
+HMODULE WINAPI SHPinDllOfCLSID(REFIID refiid);
 HRESULT WINAPI IUnknown_QueryStatus(IUnknown *lpUnknown, REFGUID pguidCmdGroup, ULONG cCmds, OLECMD *prgCmds, OLECMDTEXT* pCmdText);
 HRESULT WINAPI IUnknown_Exec(IUnknown* lpUnknown, REFGUID pguidCmdGroup, DWORD nCmdID, DWORD nCmdexecopt, VARIANT* pvaIn, VARIANT* pvaOut);
 LONG WINAPI SHSetWindowBits(HWND hwnd, INT offset, UINT wMask, UINT wFlags);