php подключиться к accdb

сервер denwer на винде 7. в php.ini extension=php_pdo_odbc.dll
файл base2020.accdb. Подключаюсь:

$dbaccess = new PDO("odbc:DRIVER={Microsoft Access Driver (*.mdb, *.accdb)};DBQ=" .$dbpath. ";Uid=; Pwd=;");

ошибка:
SQLSTATE[HY024] SQLDriverConnect: -1023 [Microsoft][ODBC Microsoft Access Driver] '(unknown)' is not a valid path. Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides.

$dbpath="db/base2020.accdb"
file_exists($dbpath) = true;

как подключиться?