diff --git a/src/mu-store-priv.hh b/src/mu-store-priv.hh
index f60e4821..e8fa7594 100644
--- a/src/mu-store-priv.hh
+++ b/src/mu-store-priv.hh
@@ -47,32 +47,20 @@ private:
 
 
 struct _MuStore {
+public:
+	/* create a read-write MuStore */
+	_MuStore (const char *path, const char *contacts_path, bool rebuild) {
 
-/* by default, use transactions of 30000 messages */
-#define MU_STORE_DEFAULT_BATCH_SIZE 30000
-	/* http://article.gmane.org/gmane.comp.search.xapian.general/3656 */
-#define MU_STORE_MAX_TERM_LENGTH 240
+		init (path, contacts_path, rebuild, false);
 
-	_MuStore (const char *path, const char *contacts_path, bool read_only):
-		_in_transaction (false), _processed (0),
-		_batch_size(MU_STORE_DEFAULT_BATCH_SIZE),
-		_contacts(0), _path (0), _version(0),
-		_db(0), _read_only(read_only), _ref_count (1) {
-
-		if (!check_path ())
-			throw MuStoreError (MU_ERROR_FILE, "invalid_path");
-
-		_path = g_strdup (path);
-
-		if (read_only)
-			_db = new Xapian::Database (path);
+		if (rebuild)
+			_db = new Xapian::WritableDatabase
+				(path, Xapian::DB_CREATE_OR_OVERWRITE);
 		else
 			_db = new Xapian::WritableDatabase
 				(path, Xapian::DB_CREATE_OR_OPEN);
 
-		if (!check_version ())
-			throw MuStoreError (MU_ERROR_XAPIAN_NOT_UP_TO_DATE,
-					    ("xapian db version check failed"));
+		check_set_version ();
 
 		if (contacts_path) {
 			_contacts = mu_contacts_new (contacts_path);
@@ -80,24 +68,64 @@ struct _MuStore {
 				throw MuStoreError (MU_ERROR_FILE,
 					    ("failed to init contacts cache"));
 		}
-		MU_WRITE_LOG ("%s: opened %s (batch size: %u)",
+
+		MU_WRITE_LOG ("%s: opened %s (batch size: %u) for read-write",
 			      __FUNCTION__, this->path(), batch_size());
 	}
 
+	/* create a read-only MuStore */
+	_MuStore (const char *path) {
+
+		init (path, NULL, false, false);
+
+		_db = new Xapian::Database (path);
+		if (mu_store_needs_upgrade(this))
+			throw MuStoreError (MU_ERROR_XAPIAN_NOT_UP_TO_DATE,
+					    ("store needs an upgrade"));
+
+		MU_WRITE_LOG ("%s: opened %s read-only", __FUNCTION__, this->path());
+	}
+
+	void init (const char *path, const char *contacts_path,
+		   bool rebuild, bool read_only) {
+
+		_batch_size	= DEFAULT_BATCH_SIZE;
+		_contacts       = 0;
+		_in_transaction = false;
+		_path           = path;
+		_processed	= 0;
+		_read_only      = read_only;
+		_ref_count      = 1;
+		_version        = NULL;
+	}
+
+	void check_set_version () {
+		/* check version...*/
+		gchar *version;
+		version = mu_store_get_metadata (this, MU_STORE_VERSION_KEY, NULL);
+		if (!version)
+			mu_store_set_metadata (this, MU_STORE_VERSION_KEY,
+					       MU_STORE_SCHEMA_VERSION, NULL);
+		else if (g_strcmp0 (version, MU_STORE_SCHEMA_VERSION) != 0) {
+			g_free (version);
+			throw MuStoreError (MU_ERROR_XAPIAN_NOT_UP_TO_DATE,
+					    ("store needs an upgrade"));
+		} else
+			g_free (version);
+	}
+
 	~_MuStore () {
 		try {
 			if (_ref_count != 0)
 				g_warning ("ref count != 0");
 
 			g_free (_version);
-			g_free (_path);
 
 			mu_contacts_destroy (_contacts);
-
 			if (!_read_only)
 				mu_store_flush (this);
 
-			MU_WRITE_LOG ("closing xapian database with %d documents",
+			MU_WRITE_LOG ("closing xapian database with %d document(s)",
 				      (int)db_read_only()->get_doccount());
 			delete _db;
 
@@ -105,7 +133,20 @@ struct _MuStore {
 	}
 
 	/* close the old database, and write an empty one on top of it */
-	void clear();
+	void clear () {
+		if (is_read_only())
+			throw std::runtime_error ("database is read-only");
+
+		// clear the database
+		db_writable()->close ();
+		delete _db;
+		_db = new Xapian::WritableDatabase
+			(path(), Xapian::DB_CREATE_OR_OVERWRITE);
+
+		// clear the contacts cache
+		if (_contacts)
+			mu_contacts_clear (_contacts);
+	}
 
 	/* get a unique id for this message; note, this function returns a
 	 * static buffer -- not reentrant */
@@ -116,10 +157,16 @@ struct _MuStore {
 
 	const char* version ()  {
 		g_free (_version);
-		return _version =
-			mu_store_get_metadata (this, MU_STORE_VERSION_KEY);
+		return _version = mu_store_get_metadata (this, MU_STORE_VERSION_KEY,
+							 NULL);
 	}
 
+	void set_version (const char *version)  {
+		mu_store_set_metadata (this, MU_STORE_VERSION_KEY, version, NULL);
+	}
+
+	static unsigned max_term_length() { return MAX_TERM_LENGTH; }
+
 	void begin_transaction ();
 	void commit_transaction ();
 	void rollback_transaction ();
@@ -132,12 +179,12 @@ struct _MuStore {
 
 	Xapian::Database* db_read_only() const { return _db; }
 
-	const char* path () const { return _path; }
+	const char* path () const { return _path.c_str(); }
 	bool is_read_only () const { return _read_only; }
 
 	size_t batch_size () const { return _batch_size;}
 	size_t set_batch_size (size_t n)  {
-		return _batch_size = ( n == 0) ? MU_STORE_DEFAULT_BATCH_SIZE : n;
+		return _batch_size = ( n == 0) ? DEFAULT_BATCH_SIZE : n;
 	}
 
 	bool   in_transaction () const { return _in_transaction; }
@@ -151,13 +198,12 @@ struct _MuStore {
 	guint  ref   () { return ++_ref_count; }
 	guint  unref () { return --_ref_count; }
 
+	/* by default, use transactions of 30000 messages */
+	static const unsigned DEFAULT_BATCH_SIZE = 30000;
+	/* http://article.gmane.org/gmane.comp.search.xapian.general/3656 */
+	static const unsigned MAX_TERM_LENGTH = 240;
+
 private:
-
-	bool check_version ();
-	bool check_path () {
-		return true; // FIXME
-	}
-
 	/* transaction handling */
 	bool   _in_transaction;
 	int    _processed;
@@ -166,8 +212,8 @@ private:
 	/* contacts object to cache all the contact information */
 	MuContacts *_contacts;
 
-	char *_path;
-	mutable char *_version;
+	std::string _path;
+	gchar *_version;
 
 	Xapian::Database *_db;
 	bool _read_only;
diff --git a/src/mu-store-read.cc b/src/mu-store-read.cc
index 8f3f213b..d0e03e29 100644
--- a/src/mu-store-read.cc
+++ b/src/mu-store-read.cc
@@ -39,29 +39,6 @@
 #include "mu-flags.h"
 #include "mu-contacts.h"
 
-
-bool
-_MuStore::check_version ()
-{
-	const gchar *version;
-	version = mu_store_version (this);
-
-	/* no version yet? it must be a new db then; we'll set the version */
-	if (!version)  {
-		if (!mu_store_set_metadata (this, MU_STORE_VERSION_KEY,
-					    MU_STORE_SCHEMA_VERSION)) {
-			g_warning ("failed to set database version");
-			return FALSE;
-		}
-			return TRUE; /* ok, done. */
-	}
-
-	/* we have a version, but is it the right one? */
-	return mu_store_needs_upgrade (this) ? FALSE : TRUE;
-}
-
-
-
 /* get a unique id for this message; note, this function returns a
  * static buffer -- not reentrant */
 const char*
@@ -91,14 +68,13 @@ mu_store_new_read_only (const char* xpath, GError **err)
 	g_return_val_if_fail (xpath, NULL);
 
 	try {
-		return  new _MuStore (xpath, NULL, true);
+		return new _MuStore (xpath);
 
 	} catch (const MuStoreError& merr) {
-
 		g_set_error (err, 0, merr.mu_error(), "%s",
 			     merr.what().c_str());
 
-	} MU_XAPIAN_CATCH_BLOCK_G_ERROR(err,MU_ERROR_XAPIAN);
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR(err, MU_ERROR_XAPIAN);
 
 	return NULL;
 }
@@ -113,18 +89,20 @@ mu_store_is_read_only (MuStore *store)
 		return store->is_read_only() ? TRUE : FALSE;
 
 	} MU_XAPIAN_CATCH_BLOCK_RETURN(FALSE);
+
 }
 
 
 unsigned
-mu_store_count (MuStore *store)
+mu_store_count (MuStore *store, GError **err)
 {
-	g_return_val_if_fail (store, 0);
+	g_return_val_if_fail (store, (unsigned)-1);
 
 	try {
 		return store->db_read_only()->get_doccount();
 
-	} MU_XAPIAN_CATCH_BLOCK_RETURN(0);
+ 	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN(err, MU_ERROR_XAPIAN,
+					       (unsigned)-1);
 }
 
 
@@ -148,7 +126,7 @@ mu_store_needs_upgrade (MuStore *store)
 
 
 char*
-mu_store_get_metadata (MuStore *store, const char *key)
+mu_store_get_metadata (MuStore *store, const char *key, GError **err)
 {
 	g_return_val_if_fail (store, NULL);
 	g_return_val_if_fail (key, NULL);
@@ -157,7 +135,7 @@ mu_store_get_metadata (MuStore *store, const char *key)
 		const std::string val (store->db_read_only()->get_metadata (key));
 		return val.empty() ? NULL : g_strdup (val.c_str());
 
-	} MU_XAPIAN_CATCH_BLOCK_RETURN(NULL);
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN(err, MU_ERROR_XAPIAN, NULL);
 }
 
 
@@ -171,7 +149,7 @@ mu_store_get_read_only_database (MuStore *store)
 
 
 gboolean
-mu_store_contains_message (MuStore *store, const char* path)
+mu_store_contains_message (MuStore *store, const char* path, GError **err)
 {
 	g_return_val_if_fail (store, FALSE);
 	g_return_val_if_fail (path, FALSE);
@@ -180,13 +158,14 @@ mu_store_contains_message (MuStore *store, const char* path)
 		const std::string uid (store->get_message_uid(path));
 		return store->db_read_only()->term_exists (uid) ? TRUE: FALSE;
 
-	} MU_XAPIAN_CATCH_BLOCK_RETURN (FALSE);
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN(err, MU_ERROR_XAPIAN, FALSE);
+
 }
 
 
 
 time_t
-mu_store_get_timestamp (MuStore *store, const char* msgpath)
+mu_store_get_timestamp (MuStore *store, const char* msgpath, GError **err)
 {
 	char *stampstr;
 	time_t rv;
@@ -194,7 +173,7 @@ mu_store_get_timestamp (MuStore *store, const char* msgpath)
 	g_return_val_if_fail (store, 0);
 	g_return_val_if_fail (msgpath, 0);
 
-	stampstr = mu_store_get_metadata (store, msgpath);
+	stampstr = mu_store_get_metadata (store, msgpath, err);
 	if (!stampstr)
 		return (time_t)0;
 
@@ -208,7 +187,7 @@ mu_store_get_timestamp (MuStore *store, const char* msgpath)
 
 MuError
 mu_store_foreach (MuStore *self,
-		  MuStoreForeachFunc func, void *user_data)
+		  MuStoreForeachFunc func, void *user_data, GError **err)
 {
 	g_return_val_if_fail (self, MU_ERROR);
 	g_return_val_if_fail (func, MU_ERROR);
@@ -233,7 +212,8 @@ mu_store_foreach (MuStore *self,
 				return res;
 		}
 
-	} MU_XAPIAN_CATCH_BLOCK_RETURN (MU_ERROR);
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN(err, MU_ERROR_XAPIAN,
+					       MU_ERROR_XAPIAN);
 
 	return MU_OK;
 }
diff --git a/src/mu-store-write.cc b/src/mu-store-write.cc
index 80cd6683..f1a22d01 100644
--- a/src/mu-store-write.cc
+++ b/src/mu-store-write.cc
@@ -66,26 +66,6 @@ _MuStore::rollback_transaction () {
 }
 
 
-
-/* close the old database, and write an empty one on top of it */
-void
-_MuStore::clear ()
-{
-	if (is_read_only())
-		throw std::runtime_error ("database is read-only");
-
-	// clear the database
-	db_writable()->close ();
-	delete _db;
-	_db = new Xapian::WritableDatabase
-		(path(), Xapian::DB_CREATE_OR_OVERWRITE);
-
-		// clear the contacts cache
-	if (_contacts)
-		mu_contacts_clear (_contacts);
-}
-
-
 /* we cache these prefix strings, so we don't have to allocate the all
  * the time; this should save 10-20 string allocs per message */
 G_GNUC_CONST static const std::string&
@@ -143,25 +123,21 @@ add_synonyms (MuStore *store)
 
 MuStore*
 mu_store_new_writable (const char* xpath, const char *contacts_cache,
-		       GError **err)
+		       gboolean rebuild, GError **err)
 {
 	g_return_val_if_fail (xpath, NULL);
 
 	try {
-		MuStore *store;
+		try {
+			MuStore *store;
+			store = new _MuStore (xpath, contacts_cache,
+					      rebuild ? true : false);
+			add_synonyms (store);
+			return store;
 
-		store = new _MuStore (xpath, contacts_cache, false);
-		add_synonyms (store);
+		} MU_STORE_CATCH_BLOCK_RETURN(err,NULL);
 
-		return store;
-
-	} catch (const MuStoreError& merr) {
-		g_set_error (err, 0, merr.mu_error(),
-			     "%s", merr.what().c_str());
-
-	} MU_XAPIAN_CATCH_BLOCK_G_ERROR(err,MU_ERROR_XAPIAN);
-
-	return NULL;
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN (err,MU_ERROR_XAPIAN, NULL);
 }
 
 
@@ -175,30 +151,35 @@ mu_store_set_batch_size (MuStore *store, guint batchsize)
 
 
 gboolean
-mu_store_set_metadata (MuStore *store, const char *key, const char *val)
+mu_store_set_metadata (MuStore *store, const char *key, const char *val,
+		       GError **err)
 {
 	g_return_val_if_fail (store, FALSE);
 	g_return_val_if_fail (key, FALSE);
 	g_return_val_if_fail (val, FALSE);
 
 	try {
-		store->db_writable()->set_metadata (key, val);
-		return TRUE;
+		try {
+			store->db_writable()->set_metadata (key, val);
+			return TRUE;
+		} MU_STORE_CATCH_BLOCK_RETURN(err, FALSE);
 
-	} MU_XAPIAN_CATCH_BLOCK;
+	} MU_XAPIAN_CATCH_BLOCK_G_ERROR_RETURN(err, MU_ERROR_XAPIAN, FALSE);
 
-	return FALSE;
 }
 
 
 gboolean
-mu_store_clear (MuStore *store)
+mu_store_clear (MuStore *store, GError **err)
 {
 	g_return_val_if_fail (store, FALSE);
 
 	try {
-		store->clear();
-		return TRUE;
+		try {
+			store->clear();
+			return TRUE;
+
+		} MU_STORE_CATCH_BLOCK_RETURN(err, FALSE);
 
 	} MU_XAPIAN_CATCH_BLOCK_RETURN(FALSE);
 }
@@ -347,7 +328,7 @@ add_terms_values_str (Xapian::Document& doc, char *val,
 
 	if (mu_msg_field_xapian_term(mfid))
 		doc.add_term (prefix(mfid) +
-			      std::string(val, 0, MU_STORE_MAX_TERM_LENGTH));
+			      std::string(val, 0, _MuStore::MAX_TERM_LENGTH));
 }
 
 
@@ -427,15 +408,16 @@ each_part (MuMsg *msg, MuMsgPart *part, PartData *pdata)
 	if (mu_msg_part_looks_like_attachment (part, TRUE) &&
 	    (part->file_name)) {
 
-		char val[MU_STORE_MAX_TERM_LENGTH + 1];
+		char val[MuStore::MAX_TERM_LENGTH + 1];
 		strncpy (val, part->file_name, sizeof(val));
 
 		/* now, let's create a terms... */
 		mu_str_normalize_in_place (val, TRUE);
 		mu_str_ascii_xapian_escape_in_place (val);
 
-		pdata->_doc.add_term (prefix(pdata->_mfid) +
-			      std::string(val, 0, MU_STORE_MAX_TERM_LENGTH));
+		pdata->_doc.add_term
+			(prefix(pdata->_mfid) +
+			 std::string(val, 0, MuStore::MAX_TERM_LENGTH));
 	}
 }
 
@@ -563,8 +545,7 @@ each_contact_info (MuMsgContact *contact, MsgDoc *msgdoc)
 	if (!mu_str_is_empty(contact->address)) {
 		char *escaped = mu_str_ascii_xapian_escape (contact->address);
 		msgdoc->_doc->add_term
-			(std::string  (pfx + escaped, 0,
-				       MU_STORE_MAX_TERM_LENGTH));
+			(std::string  (pfx + escaped, 0, MuStore::MAX_TERM_LENGTH));
 		g_free (escaped);
 
 		/* store it also in our contacts cache */
@@ -625,6 +606,7 @@ mu_store_store_msg (MuStore *store, MuMsg *msg, gboolean replace)
 }
 
 
+/* FIXME: use GError */
 gboolean
 mu_store_store_path (MuStore *store, const char *path)
 {
@@ -688,7 +670,7 @@ mu_store_remove_path (MuStore *store, const char *msgpath)
 
 gboolean
 mu_store_set_timestamp (MuStore *store, const char* msgpath,
-			time_t stamp)
+			time_t stamp, GError **err)
 {
 	char buf[21];
 
@@ -696,7 +678,7 @@ mu_store_set_timestamp (MuStore *store, const char* msgpath,
 	g_return_val_if_fail (msgpath, FALSE);
 
 	sprintf (buf, "%" G_GUINT64_FORMAT, (guint64)stamp);
-	return mu_store_set_metadata (store, msgpath, buf);
+	return mu_store_set_metadata (store, msgpath, buf, err);
 }
 
 
diff --git a/src/mu-store.h b/src/mu-store.h
index b9fd5528..a7fdf0d1 100644
--- a/src/mu-store.h
+++ b/src/mu-store.h
@@ -42,7 +42,7 @@ typedef struct _MuStore MuStore;
  * of error; free with mu_store_unref
  */
 MuStore*  mu_store_new_writable  (const char *xpath, const char *ccachepath,
-				  GError **err)
+				  gboolean rebuild, GError **err)
                  G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;
 
 
@@ -117,7 +117,6 @@ typedef gpointer XapianDatabase;
 XapianDatabase* mu_store_get_read_only_database (MuStore *store);
 
 
-
 /**
  * set the Xapian batch size for this store. Normally, there's no need
  * to use this function as the default is good enough; however, if you
@@ -132,17 +131,16 @@ void  mu_store_set_batch_size (MuStore *store, guint batchsize);
 
 
 
-
-
 /**
  * get the numbers of documents in the database
  *
  * @param index a valid MuStore instance
+ * @param err to receive error info or NULL. err->code is MuError value
  *
- * @return the number of documents in the database; 0 in case of error
- * or an empty database
+ * @return the number of documents in the database; (unsigned)-1 in
+ * case of error
  */
-unsigned mu_store_count (MuStore *store);
+unsigned mu_store_count (MuStore *store, GError **err);
 
 /**
  * get a version string for the database; it's a const string, which
@@ -210,10 +208,12 @@ gboolean mu_store_remove_path (MuStore *store, const char* msgpath);
  *
  * @param store a store
  * @param path the message path
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return TRUE if the message exists, FALSE otherwise
  */
-gboolean mu_store_contains_message (MuStore *store,  const char* path);
+gboolean mu_store_contains_message (MuStore *store,  const char* path,
+				    GError **err);
 
 /**
  * store a timestamp for a directory
@@ -221,22 +221,24 @@ gboolean mu_store_contains_message (MuStore *store,  const char* path);
  * @param store a valid store
  * @param msgpath path to a maildir
  * @param stamp a timestamp
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return TRUE if setting the timestamp succeeded, FALSE otherwise
  */
 gboolean mu_store_set_timestamp (MuStore *store, const char* msgpath,
-				 time_t stamp);
+				 time_t stamp, GError **err);
 
 /**
  * get the timestamp for a directory
  *
  * @param store a valid store
  * @param msgpath path to a maildir
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return the timestamp, or 0 in case of error
  */
-time_t mu_store_get_timestamp (MuStore *store,
-			       const char* msgpath);
+time_t mu_store_get_timestamp (MuStore *store, const char* msgpath,
+			       GError **err);
 
 
 /**
@@ -256,6 +258,7 @@ gboolean mu_store_is_read_only (MuStore *store);
  * @param self a valid store
  * @param func a callback function to to call for each document
  * @param user_data a user pointer passed to the callback function
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return MU_OK if all went well, MU_STOP if the foreach was interrupted,
  * MU_ERROR in case of error
@@ -263,7 +266,7 @@ gboolean mu_store_is_read_only (MuStore *store);
 typedef MuError (*MuStoreForeachFunc) (const char* path,
 					      void *user_data);
 MuError  mu_store_foreach (MuStore *self, MuStoreForeachFunc func,
-			   void *user_data);
+			   void *user_data, GError **err);
 
 /**
  * set metadata for this MuStore
@@ -271,21 +274,24 @@ MuError  mu_store_foreach (MuStore *self, MuStoreForeachFunc func,
  * @param store a store
  * @param key metadata key
  * @param val metadata value
+ * @param err to receive error info or NULL. err->code is the MuError value
  *
  * @return TRUE if succeeded, FALSE otherwise
  */
-gboolean mu_store_set_metadata (MuStore *store, const char *key, const char *val);
+gboolean mu_store_set_metadata (MuStore *store, const char *key, const char *val,
+				GError **err);
 
 /**
  * get metadata for this MuStore
  *
  * @param store a store
  * @param key the metadata key
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return the value of the metadata (gfree when done with it), or
  * NULL in case of error
  */
-char* mu_store_get_metadata (MuStore *store, const char *key)
+char* mu_store_get_metadata (MuStore *store, const char *key, GError **err)
 	G_GNUC_WARN_UNUSED_RESULT;
 
 
@@ -312,18 +318,17 @@ gchar* mu_store_database_version (const gchar *xpath) G_GNUC_WARN_UNUSED_RESULT;
  */
 gboolean mu_store_needs_upgrade (MuStore *store);
 
-
-
 /**
  * clear the database, ie., remove all of the contents. This is a
  * destructive operation, but the database can be restored be doing a
  * full scan of the maildirs. Also, clear the contacts cache file
  *
  * @param store a MuStore object
+ * @param err to receive error info or NULL. err->code is MuError value
  *
  * @return TRUE if the clearing succeeded, FALSE otherwise.
  */
-gboolean mu_store_clear (MuStore *store);
+gboolean mu_store_clear (MuStore *store, GError **err);
 
 
 /**