Try to restore by means of the tool:
Lotus Notes Recovery Toolbox is powerful Lotus Notes recovery tool for curropted file so you can now fix email issues without regular backups. This program can easily fix Lotus Notes files of NSF format and offers the following:
Recovers from corrupted databases such information as: email correspondence, meetings, contacts, tasks, notebook items, todo lists;
Saves attached files and previews corrupted information with sorting;
Exports information to Lotus Notes directly, uses existing templates;
Saves repaired information into a clean database or existing one;
Saves information to a local disk or remote server, corresponding access rights are required.