It doesn't seem to be possible to somehow convert NFB backups from older Nokia phones to VCF files (contacts). However, you may have been looking to convert NBF backups as VCF contacts, something doable.
I that's the case you can use the Nokia PC Suite program to export the contacts from an .nbf file to a CSV format and then use any of the available csv to vcf converters to get your vCard contacts file.
Updated: March 7, 2017
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