diff --git a/dlls/msi/helpers.c b/dlls/msi/helpers.c
index 7357bd73c53..36cbda4c58c 100644
--- a/dlls/msi/helpers.c
+++ b/dlls/msi/helpers.c
@@ -793,7 +793,7 @@ void ui_actiondata(MSIPACKAGE *package, LPCWSTR action, MSIRECORD * record)
     msiobj_release(&row->hdr);
 }
 
-BOOL ACTION_VerifyComponentForAction( MSICOMPONENT* comp, INSTALLSTATE check )
+BOOL ACTION_VerifyComponentForAction( const MSICOMPONENT* comp, INSTALLSTATE check )
 {
     if (!comp)
         return FALSE;
@@ -807,7 +807,7 @@ BOOL ACTION_VerifyComponentForAction( MSICOMPONENT* comp, INSTALLSTATE check )
         return FALSE;
 }
 
-BOOL ACTION_VerifyFeatureForAction( MSIFEATURE* feature, INSTALLSTATE check )
+BOOL ACTION_VerifyFeatureForAction( const MSIFEATURE* feature, INSTALLSTATE check )
 {
     if (!feature)
         return FALSE;
@@ -969,7 +969,7 @@ UINT register_unique_action(MSIPACKAGE *package, LPCWSTR action)
     return ERROR_SUCCESS;
 }
 
-BOOL check_unique_action(MSIPACKAGE *package, LPCWSTR action)
+BOOL check_unique_action(const MSIPACKAGE *package, LPCWSTR action)
 {
     INT i;
 
diff --git a/dlls/msi/insert.c b/dlls/msi/insert.c
index 623359f2e1e..48706ea066a 100644
--- a/dlls/msi/insert.c
+++ b/dlls/msi/insert.c
@@ -62,7 +62,7 @@ static UINT INSERT_fetch_int( struct tagMSIVIEW *view, UINT row, UINT col, UINT
  * Merge a value_list and a record to create a second record.
  * Replace wildcard entries in the valuelist with values from the record
  */
-MSIRECORD *msi_query_merge_record( UINT fields, column_info *vl, MSIRECORD *rec )
+MSIRECORD *msi_query_merge_record( UINT fields, const column_info *vl, MSIRECORD *rec )
 {
     MSIRECORD *merged;
     DWORD wildcard_count = 1, i;
@@ -234,7 +234,7 @@ static const MSIVIEWOPS insert_ops =
     INSERT_find_matching_rows
 };
 
-static UINT count_column_info( column_info *ci )
+static UINT count_column_info( const column_info *ci )
 {
     UINT n = 0;
     for ( ; ci; ci = ci->next )
@@ -242,7 +242,7 @@ static UINT count_column_info( column_info *ci )
     return n;
 }
 
-UINT INSERT_CreateView( MSIDATABASE *db, MSIVIEW **view, LPWSTR table,
+UINT INSERT_CreateView( MSIDATABASE *db, MSIVIEW **view, LPCWSTR table,
                         column_info *columns, column_info *values, BOOL temp )
 {
     MSIINSERTVIEW *iv = NULL;
diff --git a/dlls/msi/msi.c b/dlls/msi/msi.c
index 34721dfcc3a..927c47f384a 100644
--- a/dlls/msi/msi.c
+++ b/dlls/msi/msi.c
@@ -1413,7 +1413,7 @@ INSTALLSTATE WINAPI MsiUseFeatureA( LPCSTR szProduct, LPCSTR szFeature )
  * MSI_ProvideQualifiedComponentEx [internal]
  */
 static UINT WINAPI MSI_ProvideQualifiedComponentEx(LPCWSTR szComponent,
-                LPCWSTR szQualifier, DWORD dwInstallMode, LPWSTR szProduct,
+                LPCWSTR szQualifier, DWORD dwInstallMode, LPCWSTR szProduct,
                 DWORD Unused1, DWORD Unused2, awstring *lpPathBuf,
                 DWORD* pcchPathBuf)
 {
diff --git a/dlls/msi/msipriv.h b/dlls/msi/msipriv.h
index 2d05d76d0be..c43f484dac0 100644
--- a/dlls/msi/msipriv.h
+++ b/dlls/msi/msipriv.h
@@ -587,7 +587,7 @@ extern UINT MSI_SetFeatureStates( MSIPACKAGE *package );
 /* record internals */
 extern UINT MSI_RecordSetIStream( MSIRECORD *, unsigned int, IStream *);
 extern UINT MSI_RecordGetIStream( MSIRECORD *, unsigned int, IStream **);
-extern const WCHAR *MSI_RecordGetString( MSIRECORD *, unsigned int );
+extern const WCHAR *MSI_RecordGetString( const MSIRECORD *, unsigned int );
 extern MSIRECORD *MSI_CreateRecord( unsigned int );
 extern UINT MSI_RecordSetInteger( MSIRECORD *, unsigned int, int );
 extern UINT MSI_RecordSetStringW( MSIRECORD *, unsigned int, LPCWSTR );
@@ -597,7 +597,7 @@ extern UINT MSI_RecordGetStringW( MSIRECORD * , unsigned int, LPWSTR, DWORD *);
 extern UINT MSI_RecordGetStringA( MSIRECORD *, unsigned int, LPSTR, DWORD *);
 extern int MSI_RecordGetInteger( MSIRECORD *, unsigned int );
 extern UINT MSI_RecordReadStream( MSIRECORD *, unsigned int, char *, DWORD *);
-extern unsigned int MSI_RecordGetFieldCount( MSIRECORD *rec );
+extern unsigned int MSI_RecordGetFieldCount( const MSIRECORD *rec );
 extern UINT MSI_RecordSetStream( MSIRECORD *, unsigned int, IStream * );
 extern UINT MSI_RecordDataSize( MSIRECORD *, unsigned int );
 extern UINT MSI_RecordStreamToFile( MSIRECORD *, unsigned int, LPCWSTR );
@@ -634,7 +634,7 @@ extern UINT VIEW_find_column( MSIVIEW *, LPCWSTR, UINT * );
 extern UINT MSI_SetInstallLevel( MSIPACKAGE *package, int iInstallLevel );
 
 /* package internals */
-extern MSIPACKAGE *MSI_CreatePackage( MSIDATABASE *, LPWSTR );
+extern MSIPACKAGE *MSI_CreatePackage( MSIDATABASE *, LPCWSTR );
 extern UINT MSI_OpenPackageW( LPCWSTR szPackage, MSIPACKAGE ** );
 extern UINT MSI_SetTargetPathW( MSIPACKAGE *, LPCWSTR, LPCWSTR );
 extern UINT MSI_SetPropertyW( MSIPACKAGE *, LPCWSTR, LPCWSTR );
@@ -770,14 +770,14 @@ extern void msi_free_action_script(MSIPACKAGE *package, UINT script);
 extern LPWSTR build_icon_path(MSIPACKAGE *, LPCWSTR);
 extern LPWSTR build_directory_name(DWORD , ...);
 extern BOOL create_full_pathW(const WCHAR *path);
-extern BOOL ACTION_VerifyComponentForAction(MSICOMPONENT*, INSTALLSTATE);
-extern BOOL ACTION_VerifyFeatureForAction(MSIFEATURE*, INSTALLSTATE);
+extern BOOL ACTION_VerifyComponentForAction(const MSICOMPONENT*, INSTALLSTATE);
+extern BOOL ACTION_VerifyFeatureForAction(const MSIFEATURE*, INSTALLSTATE);
 extern void reduce_to_longfilename(WCHAR*);
 extern void reduce_to_shortfilename(WCHAR*);
 extern LPWSTR create_component_advertise_string(MSIPACKAGE*, MSICOMPONENT*, LPCWSTR);
 extern void ACTION_UpdateComponentStates(MSIPACKAGE *package, LPCWSTR szFeature);
 extern UINT register_unique_action(MSIPACKAGE *, LPCWSTR);
-extern BOOL check_unique_action(MSIPACKAGE *, LPCWSTR);
+extern BOOL check_unique_action(const MSIPACKAGE *, LPCWSTR);
 extern WCHAR* generate_error_string(MSIPACKAGE *, UINT, DWORD, ... );
 extern UINT msi_create_component_directories( MSIPACKAGE *package );
 extern void msi_ui_error( DWORD msg_id, DWORD type );
diff --git a/dlls/msi/package.c b/dlls/msi/package.c
index 77dbaffe914..e93ee036a86 100644
--- a/dlls/msi/package.c
+++ b/dlls/msi/package.c
@@ -587,7 +587,7 @@ static MSIPACKAGE *msi_alloc_package( void )
     return package;
 }
 
-MSIPACKAGE *MSI_CreatePackage( MSIDATABASE *db, LPWSTR base_url )
+MSIPACKAGE *MSI_CreatePackage( MSIDATABASE *db, LPCWSTR base_url )
 {
     static const WCHAR szLevel[] = { 'U','I','L','e','v','e','l',0 };
     static const WCHAR szpi[] = {'%','i',0};
diff --git a/dlls/msi/query.h b/dlls/msi/query.h
index 2bf8955d1a8..6cb7709b0e5 100644
--- a/dlls/msi/query.h
+++ b/dlls/msi/query.h
@@ -111,7 +111,7 @@ UINT WHERE_CreateView( MSIDATABASE *db, MSIVIEW **view, MSIVIEW *table,
 UINT CREATE_CreateView( MSIDATABASE *db, MSIVIEW **view, LPWSTR table,
                         column_info *col_info, BOOL hold );
 
-UINT INSERT_CreateView( MSIDATABASE *db, MSIVIEW **view, LPWSTR table,
+UINT INSERT_CreateView( MSIDATABASE *db, MSIVIEW **view, LPCWSTR table,
                         column_info *columns, column_info *values, BOOL temp );
 
 UINT UPDATE_CreateView( MSIDATABASE *db, MSIVIEW **, LPWSTR table,
@@ -128,7 +128,7 @@ UINT STREAMS_CreateView( MSIDATABASE *db, MSIVIEW **view );
 
 int sqliteGetToken(const WCHAR *z, int *tokenType);
 
-MSIRECORD *msi_query_merge_record( UINT fields, column_info *vl, MSIRECORD *rec );
+MSIRECORD *msi_query_merge_record( UINT fields, const column_info *vl, MSIRECORD *rec );
 
 UINT msi_create_table( MSIDATABASE *db, LPCWSTR name, column_info *col_info,
                        BOOL persistent, MSITABLE **table_ret);
diff --git a/dlls/msi/record.c b/dlls/msi/record.c
index fed7bf43424..159f7d17db4 100644
--- a/dlls/msi/record.c
+++ b/dlls/msi/record.c
@@ -106,7 +106,7 @@ MSIHANDLE WINAPI MsiCreateRecord( unsigned int cParams )
     return ret;
 }
 
-unsigned int MSI_RecordGetFieldCount( MSIRECORD *rec )
+unsigned int MSI_RecordGetFieldCount( const MSIRECORD *rec )
 {
     return rec->count;
 }
@@ -393,7 +393,7 @@ UINT WINAPI MsiRecordGetStringA(MSIHANDLE handle, unsigned int iField,
     return ret;
 }
 
-const WCHAR *MSI_RecordGetString( MSIRECORD *rec, unsigned int iField )
+const WCHAR *MSI_RecordGetString( const MSIRECORD *rec, unsigned int iField )
 {
     if( iField > rec->count )
         return NULL;