I get above error message when exporting records from any module (account, task, project, etc..) Running on AWS - T2 medium. Odoo 11 CE from BItnami.  I have updated all modules to latest versions.  This problem was also reported by other users:

https://www.odoo.com/forum/help-1/question/data-will-not-export-134247

https://github.com/odoo/odoo/issues/24145

https://community.bitnami.com/t/odoo-11-export-to-excel-cvs-error-copy-from-cannot-be-used-with-an-asynchronous-callback/57528

The full error message is:

{"code": 200, "message": "Odoo Server Error", "data": {"name": "psycopg2.ProgrammingError", "debug": "Traceback (most recent call last):\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/addons/web/controllers/main.py\", line 78, in wrap\n    return f(*args, **kwargs)\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/addons/web/controllers/main.py\", line 1421, in index\n    return self.base(data, token)\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/addons/web/controllers/main.py\", line 1403, in base\n    import_data = records.export_data(field_names, self.raw_data).get('datas',[])\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/models.py\", line 794, in export_data\n    return {'datas': self._export_rows(fields_to_export)}\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/models.py\", line 718, in _export_rows\n    xids = dict(self.__ensure_xml_id(skip=['id'] not in fields))\n  File \"/opt/bitnami/apps/odoo/lib/odoo-11.0.post20180518-py3.6.egg/odoo/models.py\", line 682, in __ensure_xml_id\n    columns=fields,\npsycopg2.ProgrammingError: copy_from cannot be used with an asynchronous callback.\n", "message": "copy_from cannot be used with an asynchronous callback.", "arguments": ["copy_from cannot be used with an asynchronous callback."], "exception_type": "internal_error"}}

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