diff --git a/dlls/msi/Makefile.in b/dlls/msi/Makefile.in
index 37c9a7ad4e0..1a17d7e518a 100644
--- a/dlls/msi/Makefile.in
+++ b/dlls/msi/Makefile.in
@@ -1,8 +1,10 @@
 MODULE    = msi.dll
 IMPORTLIB = msi
-IMPORTS   = uuid urlmon wininet comctl32 shell32 shlwapi cabinet oleaut32 ole32 version user32 gdi32 advapi32
+IMPORTS   = uuid urlmon wininet comctl32 shell32 shlwapi cabinet oleaut32 ole32 version user32 gdi32 advapi32 rpcrt4
 DELAYIMPORTS = odbccp32 wintrust crypt32 imagehlp mspatcha
 
+EXTRAIDLFLAGS = --prefix-server=s_
+
 C_SRCS = \
 	action.c \
 	alter.c \
diff --git a/dlls/msi/custom.c b/dlls/msi/custom.c
index f9976a04aee..12fe53ead10 100644
--- a/dlls/msi/custom.c
+++ b/dlls/msi/custom.c
@@ -486,35 +486,18 @@ static void handle_msi_break(LPCSTR target)
     DebugBreak();
 }
 
-#ifdef __i386__
-extern UINT CUSTOMPROC_wrapper( MsiCustomActionEntryPoint proc, MSIHANDLE handle );
-__ASM_GLOBAL_FUNC( CUSTOMPROC_wrapper,
-    "pushl %ebp\n\t"
-    __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
-    __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
-    "movl %esp,%ebp\n\t"
-    __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
-    "subl $4,%esp\n\t"
-    "pushl 12(%ebp)\n\t"
-    "movl 8(%ebp),%eax\n\t"
-    "call *%eax\n\t"
-    "leave\n\t"
-    __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
-    __ASM_CFI(".cfi_same_value %ebp\n\t")
-    "ret" )
-#else
-static inline UINT CUSTOMPROC_wrapper( MsiCustomActionEntryPoint proc, MSIHANDLE handle )
-{
-    return proc(handle);
-}
-#endif
+static WCHAR ncalrpcW[] = {'n','c','a','l','r','p','c',0};
+static WCHAR endpoint_lrpcW[] = {'m','s','i',0};
 
-static DWORD ACTION_CallDllFunction( const GUID *guid )
+UINT __wine_msi_call_dll_function(const GUID *guid)
 {
     MsiCustomActionEntryPoint fn;
     MSIHANDLE remote_package = 0;
+    RPC_WSTR binding_str;
     MSIHANDLE hPackage;
+    RPC_STATUS status;
     HANDLE hModule;
+    HANDLE thread;
     LPWSTR dll;
     LPSTR proc;
     INT type;
@@ -522,6 +505,23 @@ static DWORD ACTION_CallDllFunction( const GUID *guid )
 
     TRACE("%s\n", debugstr_guid( guid ));
 
+    status = RpcStringBindingComposeW(NULL, ncalrpcW, NULL, endpoint_lrpcW, NULL, &binding_str);
+    if (status != RPC_S_OK)
+    {
+        ERR("RpcStringBindingCompose failed: %#x\n", status);
+        return status;
+    }
+    status = RpcBindingFromStringBindingW(binding_str, &rpc_handle);
+    if (status != RPC_S_OK)
+    {
+        ERR("RpcBindingFromStringBinding failed: %#x\n", status);
+        return status;
+    }
+    RpcStringFreeW(&binding_str);
+
+    /* We need this to unmarshal streams, and some apps expect it to be present. */
+    CoInitializeEx(NULL, COINIT_MULTITHREADED);
+
     r = remote_GetActionInfo(guid, &type, &dll, &proc, &remote_package);
     if (r != ERROR_SUCCESS)
         return r;
@@ -544,7 +544,9 @@ static DWORD ACTION_CallDllFunction( const GUID *guid )
 
             __TRY
             {
-                r = CUSTOMPROC_wrapper( fn, hPackage );
+                thread = CreateThread(NULL, 0, (void *)fn, (void *)(ULONG_PTR) hPackage, 0, NULL);
+                WaitForSingleObject(thread, INFINITE);
+                GetExitCodeThread(thread, &r);
             }
             __EXCEPT_PAGE_FAULT
             {
@@ -568,17 +570,56 @@ static DWORD ACTION_CallDllFunction( const GUID *guid )
     midl_user_free(dll);
     midl_user_free(proc);
 
+    CoUninitialize();
+
+    RpcBindingFree(&rpc_handle);
+
     return r;
 }
 
 static DWORD WINAPI DllThread( LPVOID arg )
 {
-    LPGUID guid = arg;
-    DWORD rc = 0;
+    WCHAR buffer[64] = {'m','s','i','e','x','e','c','.','e','x','e',' ','-','E','m','b','e','d','d','i','n','g',' ',0};
+    PROCESS_INFORMATION pi = {0};
+    STARTUPINFOW si = {0};
+    RPC_STATUS status;
+    GUID *guid = arg;
+    DWORD rc;
 
     TRACE("custom action (%x) started\n", GetCurrentThreadId() );
 
-    rc = ACTION_CallDllFunction( guid );
+    CoInitializeEx(NULL, COINIT_MULTITHREADED); /* needed to marshal streams */
+
+    status = RpcServerUseProtseqEpW(ncalrpcW, RPC_C_PROTSEQ_MAX_REQS_DEFAULT, endpoint_lrpcW, NULL);
+    if (status != RPC_S_OK)
+    {
+        ERR("RpcServerUseProtseqEp failed: %#x\n", status);
+        return status;
+    }
+
+    status = RpcServerRegisterIfEx(s_IWineMsiRemote_v0_0_s_ifspec, NULL, NULL,
+        RPC_IF_AUTOLISTEN, RPC_C_LISTEN_MAX_CALLS_DEFAULT, NULL);
+    if (status != RPC_S_OK)
+    {
+        ERR("RpcServerRegisterIfEx failed: %#x\n", status);
+        return status;
+    }
+
+    StringFromGUID2(guid, buffer + strlenW(buffer), 39);
+    CreateProcessW(NULL, buffer, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi);
+    WaitForSingleObject(pi.hProcess, INFINITE);
+    GetExitCodeProcess(pi.hProcess, &rc);
+    CloseHandle(pi.hProcess);
+    CloseHandle(pi.hThread);
+
+    status = RpcServerUnregisterIf(s_IWineMsiRemote_v0_0_s_ifspec, NULL, FALSE);
+    if (status != RPC_S_OK)
+    {
+        ERR("RpcServerUnregisterIf failed: %#x\n", status);
+        return status;
+    }
+
+    CoUninitialize();
 
     TRACE("custom action (%x) returned %i\n", GetCurrentThreadId(), rc );
 
@@ -1343,7 +1384,7 @@ void ACTION_FinishCustomActions(const MSIPACKAGE* package)
     LeaveCriticalSection( &msi_custom_action_cs );
 }
 
-UINT __cdecl remote_GetActionInfo(const GUID *guid, int *type, LPWSTR *dll, LPSTR *func, MSIHANDLE *hinst)
+UINT __cdecl s_remote_GetActionInfo(const GUID *guid, int *type, LPWSTR *dll, LPSTR *func, MSIHANDLE *hinst)
 {
     msi_custom_action_info *info;
 
diff --git a/dlls/msi/database.c b/dlls/msi/database.c
index 4a0559366dc..ef0221d2b85 100644
--- a/dlls/msi/database.c
+++ b/dlls/msi/database.c
@@ -1906,12 +1906,12 @@ MSIDBSTATE WINAPI MsiGetDatabaseState( MSIHANDLE handle )
     return ret;
 }
 
-MSICONDITION __cdecl remote_DatabaseIsTablePersistent(MSIHANDLE db, LPCWSTR table)
+MSICONDITION __cdecl s_remote_DatabaseIsTablePersistent(MSIHANDLE db, LPCWSTR table)
 {
     return MsiDatabaseIsTablePersistentW(db, table);
 }
 
-UINT __cdecl remote_DatabaseGetPrimaryKeys(MSIHANDLE db, LPCWSTR table, struct wire_record **rec)
+UINT __cdecl s_remote_DatabaseGetPrimaryKeys(MSIHANDLE db, LPCWSTR table, struct wire_record **rec)
 {
     MSIHANDLE handle;
     UINT r = MsiDatabaseGetPrimaryKeysW(db, table, &handle);
@@ -1922,12 +1922,12 @@ UINT __cdecl remote_DatabaseGetPrimaryKeys(MSIHANDLE db, LPCWSTR table, struct w
     return r;
 }
 
-UINT __cdecl remote_DatabaseGetSummaryInformation(MSIHANDLE db, UINT updatecount, MSIHANDLE *suminfo)
+UINT __cdecl s_remote_DatabaseGetSummaryInformation(MSIHANDLE db, UINT updatecount, MSIHANDLE *suminfo)
 {
     return MsiGetSummaryInformationW(db, NULL, updatecount, suminfo);
 }
 
-UINT __cdecl remote_DatabaseOpenView(MSIHANDLE db, LPCWSTR query, MSIHANDLE *view)
+UINT __cdecl s_remote_DatabaseOpenView(MSIHANDLE db, LPCWSTR query, MSIHANDLE *view)
 {
     return MsiDatabaseOpenViewW(db, query, view);
 }
diff --git a/dlls/msi/handle.c b/dlls/msi/handle.c
index 1002f9d969b..0881833ff68 100644
--- a/dlls/msi/handle.c
+++ b/dlls/msi/handle.c
@@ -344,7 +344,7 @@ UINT WINAPI MsiCloseAllHandles(void)
     return n;
 }
 
-UINT __cdecl remote_CloseHandle(MSIHANDLE handle)
+UINT __cdecl s_remote_CloseHandle(MSIHANDLE handle)
 {
     return MsiCloseHandle(handle);
 }
diff --git a/dlls/msi/msi.spec b/dlls/msi/msi.spec
index 4288c9d408f..aecba1b1b38 100644
--- a/dlls/msi/msi.spec
+++ b/dlls/msi/msi.spec
@@ -294,3 +294,5 @@
 @ stdcall -private DllGetClassObject(ptr ptr ptr)
 @ stdcall -private DllRegisterServer()
 @ stdcall -private DllUnregisterServer()
+
+@ cdecl __wine_msi_call_dll_function(ptr)
diff --git a/dlls/msi/msiquery.c b/dlls/msi/msiquery.c
index 42ee8c79d02..7dcfa7fbfd8 100644
--- a/dlls/msi/msiquery.c
+++ b/dlls/msi/msiquery.c
@@ -1093,12 +1093,12 @@ MSICONDITION WINAPI MsiDatabaseIsTablePersistentW(
     return r;
 }
 
-UINT __cdecl remote_ViewClose(MSIHANDLE view)
+UINT __cdecl s_remote_ViewClose(MSIHANDLE view)
 {
     return MsiViewClose(view);
 }
 
-UINT __cdecl remote_ViewExecute(MSIHANDLE view, struct wire_record *remote_rec)
+UINT __cdecl s_remote_ViewExecute(MSIHANDLE view, struct wire_record *remote_rec)
 {
     MSIHANDLE rec = 0;
     UINT r;
@@ -1112,7 +1112,7 @@ UINT __cdecl remote_ViewExecute(MSIHANDLE view, struct wire_record *remote_rec)
     return r;
 }
 
-UINT __cdecl remote_ViewFetch(MSIHANDLE view, struct wire_record **rec)
+UINT __cdecl s_remote_ViewFetch(MSIHANDLE view, struct wire_record **rec)
 {
     MSIHANDLE handle;
     UINT r = MsiViewFetch(view, &handle);
@@ -1123,7 +1123,7 @@ UINT __cdecl remote_ViewFetch(MSIHANDLE view, struct wire_record **rec)
     return r;
 }
 
-UINT __cdecl remote_ViewGetColumnInfo(MSIHANDLE view, MSICOLINFO info, struct wire_record **rec)
+UINT __cdecl s_remote_ViewGetColumnInfo(MSIHANDLE view, MSICOLINFO info, struct wire_record **rec)
 {
     MSIHANDLE handle;
     UINT r = MsiViewGetColumnInfo(view, info, &handle);
@@ -1134,7 +1134,7 @@ UINT __cdecl remote_ViewGetColumnInfo(MSIHANDLE view, MSICOLINFO info, struct wi
     return r;
 }
 
-UINT __cdecl remote_ViewModify(MSIHANDLE view, MSIMODIFY mode,
+UINT __cdecl s_remote_ViewModify(MSIHANDLE view, MSIMODIFY mode,
     struct wire_record *remote_rec, struct wire_record **remote_refreshed)
 {
     MSIHANDLE handle = 0;
diff --git a/dlls/msi/package.c b/dlls/msi/package.c
index 067e5711bf5..a2fa785e50a 100644
--- a/dlls/msi/package.c
+++ b/dlls/msi/package.c
@@ -2421,12 +2421,12 @@ UINT WINAPI MsiGetPropertyW( MSIHANDLE hInstall, LPCWSTR szName,
     return MSI_GetProperty( hInstall, szName, &val, pchValueBuf );
 }
 
-MSIHANDLE __cdecl remote_GetActiveDatabase(MSIHANDLE hinst)
+MSIHANDLE __cdecl s_remote_GetActiveDatabase(MSIHANDLE hinst)
 {
     return MsiGetActiveDatabase(hinst);
 }
 
-UINT __cdecl remote_GetProperty(MSIHANDLE hinst, LPCWSTR property, LPWSTR *value, DWORD *size)
+UINT __cdecl s_remote_GetProperty(MSIHANDLE hinst, LPCWSTR property, LPWSTR *value, DWORD *size)
 {
     WCHAR empty[1];
     UINT r;
@@ -2444,12 +2444,12 @@ UINT __cdecl remote_GetProperty(MSIHANDLE hinst, LPCWSTR property, LPWSTR *value
     return r;
 }
 
-UINT __cdecl remote_SetProperty(MSIHANDLE hinst, LPCWSTR property, LPCWSTR value)
+UINT __cdecl s_remote_SetProperty(MSIHANDLE hinst, LPCWSTR property, LPCWSTR value)
 {
     return MsiSetPropertyW(hinst, property, value);
 }
 
-int __cdecl remote_ProcessMessage(MSIHANDLE hinst, INSTALLMESSAGE message, struct wire_record *remote_rec)
+int __cdecl s_remote_ProcessMessage(MSIHANDLE hinst, INSTALLMESSAGE message, struct wire_record *remote_rec)
 {
     MSIHANDLE rec;
     int ret;
@@ -2464,17 +2464,17 @@ int __cdecl remote_ProcessMessage(MSIHANDLE hinst, INSTALLMESSAGE message, struc
     return ret;
 }
 
-UINT __cdecl remote_DoAction(MSIHANDLE hinst, LPCWSTR action)
+UINT __cdecl s_remote_DoAction(MSIHANDLE hinst, LPCWSTR action)
 {
     return MsiDoActionW(hinst, action);
 }
 
-UINT __cdecl remote_Sequence(MSIHANDLE hinst, LPCWSTR table, int sequence)
+UINT __cdecl s_remote_Sequence(MSIHANDLE hinst, LPCWSTR table, int sequence)
 {
     return MsiSequenceW(hinst, table, sequence);
 }
 
-UINT __cdecl remote_GetTargetPath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value)
+UINT __cdecl s_remote_GetTargetPath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value)
 {
     WCHAR empty[1];
     DWORD size = 0;
@@ -2491,12 +2491,12 @@ UINT __cdecl remote_GetTargetPath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value
     return r;
 }
 
-UINT __cdecl remote_SetTargetPath(MSIHANDLE hinst, LPCWSTR folder, LPCWSTR value)
+UINT __cdecl s_remote_SetTargetPath(MSIHANDLE hinst, LPCWSTR folder, LPCWSTR value)
 {
     return MsiSetTargetPathW(hinst, folder, value);
 }
 
-UINT __cdecl remote_GetSourcePath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value)
+UINT __cdecl s_remote_GetSourcePath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value)
 {
     WCHAR empty[1];
     DWORD size = 1;
@@ -2513,49 +2513,49 @@ UINT __cdecl remote_GetSourcePath(MSIHANDLE hinst, LPCWSTR folder, LPWSTR *value
     return r;
 }
 
-BOOL __cdecl remote_GetMode(MSIHANDLE hinst, MSIRUNMODE mode)
+BOOL __cdecl s_remote_GetMode(MSIHANDLE hinst, MSIRUNMODE mode)
 {
     return MsiGetMode(hinst, mode);
 }
 
-UINT __cdecl remote_SetMode(MSIHANDLE hinst, MSIRUNMODE mode, BOOL state)
+UINT __cdecl s_remote_SetMode(MSIHANDLE hinst, MSIRUNMODE mode, BOOL state)
 {
     return MsiSetMode(hinst, mode, state);
 }
 
-UINT __cdecl remote_GetFeatureState(MSIHANDLE hinst, LPCWSTR feature,
+UINT __cdecl s_remote_GetFeatureState(MSIHANDLE hinst, LPCWSTR feature,
                                     INSTALLSTATE *installed, INSTALLSTATE *action)
 {
     return MsiGetFeatureStateW(hinst, feature, installed, action);
 }
 
-UINT __cdecl remote_SetFeatureState(MSIHANDLE hinst, LPCWSTR feature, INSTALLSTATE state)
+UINT __cdecl s_remote_SetFeatureState(MSIHANDLE hinst, LPCWSTR feature, INSTALLSTATE state)
 {
     return MsiSetFeatureStateW(hinst, feature, state);
 }
 
-UINT __cdecl remote_GetComponentState(MSIHANDLE hinst, LPCWSTR component,
+UINT __cdecl s_remote_GetComponentState(MSIHANDLE hinst, LPCWSTR component,
                                       INSTALLSTATE *installed, INSTALLSTATE *action)
 {
     return MsiGetComponentStateW(hinst, component, installed, action);
 }
 
-UINT __cdecl remote_SetComponentState(MSIHANDLE hinst, LPCWSTR component, INSTALLSTATE state)
+UINT __cdecl s_remote_SetComponentState(MSIHANDLE hinst, LPCWSTR component, INSTALLSTATE state)
 {
     return MsiSetComponentStateW(hinst, component, state);
 }
 
-LANGID __cdecl remote_GetLanguage(MSIHANDLE hinst)
+LANGID __cdecl s_remote_GetLanguage(MSIHANDLE hinst)
 {
     return MsiGetLanguage(hinst);
 }
 
-UINT __cdecl remote_SetInstallLevel(MSIHANDLE hinst, int level)
+UINT __cdecl s_remote_SetInstallLevel(MSIHANDLE hinst, int level)
 {
     return MsiSetInstallLevel(hinst, level);
 }
 
-UINT __cdecl remote_FormatRecord(MSIHANDLE hinst, struct wire_record *remote_rec, LPWSTR *value)
+UINT __cdecl s_remote_FormatRecord(MSIHANDLE hinst, struct wire_record *remote_rec, LPWSTR *value)
 {
     WCHAR empty[1];
     DWORD size = 0;
@@ -2578,18 +2578,18 @@ UINT __cdecl remote_FormatRecord(MSIHANDLE hinst, struct wire_record *remote_rec
     return r;
 }
 
-MSICONDITION __cdecl remote_EvaluateCondition(MSIHANDLE hinst, LPCWSTR condition)
+MSICONDITION __cdecl s_remote_EvaluateCondition(MSIHANDLE hinst, LPCWSTR condition)
 {
     return MsiEvaluateConditionW(hinst, condition);
 }
 
-UINT __cdecl remote_GetFeatureCost(MSIHANDLE hinst, LPCWSTR feature,
+UINT __cdecl s_remote_GetFeatureCost(MSIHANDLE hinst, LPCWSTR feature,
     MSICOSTTREE cost_tree, INSTALLSTATE state, INT *cost)
 {
     return MsiGetFeatureCostW(hinst, feature, cost_tree, state, cost);
 }
 
-UINT __cdecl remote_EnumComponentCosts(MSIHANDLE hinst, LPCWSTR component,
+UINT __cdecl s_remote_EnumComponentCosts(MSIHANDLE hinst, LPCWSTR component,
     DWORD index, INSTALLSTATE state, LPWSTR drive, INT *cost, INT *temp)
 {
     DWORD size = 3;
diff --git a/dlls/msi/tests/custom.c b/dlls/msi/tests/custom.c
index 35b3d71f52b..04946d907d3 100644
--- a/dlls/msi/tests/custom.c
+++ b/dlls/msi/tests/custom.c
@@ -993,7 +993,7 @@ UINT WINAPI main_test(MSIHANDLE hinst)
 
     /* Test for an MTA apartment */
     hr = CoCreateInstance(&CLSID_XMLDocument, NULL, CLSCTX_INPROC_SERVER, &IID_IUnknown, (void **)&unk);
-    todo_wine_ok(hinst, hr == S_OK, "CoCreateInstance failed with %08x\n", hr);
+    ok(hinst, hr == S_OK, "CoCreateInstance failed with %08x\n", hr);
 
     if (unk) IUnknown_Release(unk);
 
diff --git a/dlls/msi/winemsi.idl b/dlls/msi/winemsi.idl
index 8af175999b8..50f62fcbfd8 100644
--- a/dlls/msi/winemsi.idl
+++ b/dlls/msi/winemsi.idl
@@ -18,6 +18,8 @@
  */
 
 #pragma makedep header
+#pragma makedep client
+#pragma makedep server
 
 import "objidl.idl";
 
@@ -55,7 +57,8 @@ struct wire_record {
 };
 
 [
-    uuid(56D58B64-8780-4c22-A8BC-8B0B29E4A9F8)
+    uuid(56D58B64-8780-4c22-A8BC-8B0B29E4A9F8),
+    implicit_handle(handle_t rpc_handle)
 ]
 interface IWineMsiRemote
 {
diff --git a/programs/msiexec/msiexec.c b/programs/msiexec/msiexec.c
index 8dcd216380e..2ed055771f6 100644
--- a/programs/msiexec/msiexec.c
+++ b/programs/msiexec/msiexec.c
@@ -393,10 +393,13 @@ static DWORD DoUnregServer(void)
     return ret;
 }
 
-static INT DoEmbedding( LPWSTR key )
+extern UINT __wine_msi_call_dll_function(GUID *guid);
+
+static int DoEmbedding(LPCWSTR key)
 {
-	printf("Remote custom actions are not supported yet\n");
-	return 1;
+    GUID guid;
+    CLSIDFromString(key, &guid);
+    return __wine_msi_call_dll_function(&guid);
 }
 
 /*