ERROR

when i am trying to add and edit or save any thing at my admin back end its showing ERROR
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PDOException: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'keys.i18n_string' doesn't exist: SELECT i.*, s.source AS source, s.version AS version, s.location AS location FROM {i18n_string} i LEFT OUTER JOIN {locales_source} s ON i.lid = s.lid WHERE (i.type = :db_condition_placeholder_0) AND (i.objectid = :db_condition_placeholder_1) AND (i.textgroup = :db_condition_placeholder_2) ; Array ( [:db_condition_placeholder_0] => type [:db_condition_placeholder_1] => forum [:db_condition_placeholder_2] => node ) in i18n_string_load_multiple() (line 459 of C:\xampp\htdocs\keys\sites\all\modules\i18n\i18n_string\i18n_string.module).
The website encountered an unexpected error. Please try again later.
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