.nbu files are the backup files created when you create the backup for your Nokia Mobile. It is created using Nokia PC suite and later can be restored to your phone. Only problem is we can’t open the .nbu files without any nokia device.
To overcome this problem we have one software called NOKI. From their site:
Noki is a utility to explore and extract Phone book, SMS, Calendar, Memo, Bookmark and other user files from the backup file of Nokia phone (using Nokia PC Suite).
- Supports .nbu, .nfb and .nfc.
- contacts.cdb: Symbian Contacts Database for all Symbian phones (include Nokia, Siemens, Sony Ericsson etc.).
- backup.arc: mass storage/SD card backup file.
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