diff --git a/dll/win32/msi/suminfo.c b/dll/win32/msi/suminfo.c
index 41ea4e44122..ec676e46e00 100644
--- a/dll/win32/msi/suminfo.c
+++ b/dll/win32/msi/suminfo.c
@@ -892,26 +892,32 @@ static UINT set_prop( MSISUMMARYINFO *si, UINT uiProperty, UINT type,
     return ERROR_SUCCESS;
 }
 
+static UINT msi_set_prop( MSISUMMARYINFO *si, UINT uiProperty, UINT uiDataType,
+                          INT iValue, FILETIME *pftValue, awcstring *str )
+{
+    UINT type = get_type( uiProperty );
+    if( type == VT_EMPTY || type != uiDataType )
+        return ERROR_DATATYPE_MISMATCH;
+
+    if( uiDataType == VT_LPSTR && !str->str.a )
+        return ERROR_INVALID_PARAMETER;
+
+    if( uiDataType == VT_FILETIME && !pftValue )
+        return ERROR_INVALID_PARAMETER;
+
+    return set_prop( si, uiProperty, type, iValue, pftValue, str );
+}
+
 UINT WINAPI MsiSummaryInfoSetPropertyW( MSIHANDLE handle, UINT uiProperty, UINT uiDataType,
                                         INT iValue, FILETIME *pftValue, LPCWSTR szValue )
 {
     awcstring str;
     MSISUMMARYINFO *si;
-    UINT type, ret;
+    UINT ret;
 
     TRACE("%u, %u, %u, %d, %p, %s\n", handle, uiProperty, uiDataType, iValue, pftValue,
           debugstr_w(szValue) );
 
-    type = get_type( uiProperty );
-    if( type == VT_EMPTY || type != uiDataType )
-        return ERROR_DATATYPE_MISMATCH;
-
-    if( uiDataType == VT_LPSTR && !szValue )
-        return ERROR_INVALID_PARAMETER;
-
-    if( uiDataType == VT_FILETIME && !pftValue )
-        return ERROR_INVALID_PARAMETER;
-
     if (!(si = msihandle2msiinfo( handle, MSIHANDLETYPE_SUMMARYINFO )))
     {
         MSIHANDLE remote;
@@ -928,7 +934,7 @@ UINT WINAPI MsiSummaryInfoSetPropertyW( MSIHANDLE handle, UINT uiProperty, UINT
     str.unicode = TRUE;
     str.str.w = szValue;
 
-    ret = set_prop( si, uiProperty, type, iValue, pftValue, &str );
+    ret = msi_set_prop( si, uiProperty, uiDataType, iValue, pftValue, &str );
     msiobj_release( &si->hdr );
     return ret;
 }
@@ -938,21 +944,11 @@ UINT WINAPI MsiSummaryInfoSetPropertyA( MSIHANDLE handle, UINT uiProperty, UINT
 {
     awcstring str;
     MSISUMMARYINFO *si;
-    UINT type, ret;
+    UINT ret;
 
     TRACE("%u, %u, %u, %d, %p, %s\n", handle, uiProperty, uiDataType, iValue, pftValue,
           debugstr_a(szValue) );
 
-    type = get_type( uiProperty );
-    if( type == VT_EMPTY || type != uiDataType )
-        return ERROR_DATATYPE_MISMATCH;
-
-    if( uiDataType == VT_LPSTR && !szValue )
-        return ERROR_INVALID_PARAMETER;
-
-    if( uiDataType == VT_FILETIME && !pftValue )
-        return ERROR_INVALID_PARAMETER;
-
     if (!(si = msihandle2msiinfo( handle, MSIHANDLETYPE_SUMMARYINFO )))
     {
         MSIHANDLE remote;
@@ -969,7 +965,7 @@ UINT WINAPI MsiSummaryInfoSetPropertyA( MSIHANDLE handle, UINT uiProperty, UINT
     str.unicode = FALSE;
     str.str.a = szValue;
 
-    ret = set_prop( si, uiProperty, uiDataType, iValue, pftValue, &str );
+    ret = msi_set_prop( si, uiProperty, uiDataType, iValue, pftValue, &str );
     msiobj_release( &si->hdr );
     return ret;
 }