Outlook sometimes exports VCF with duplicates if the same contact exists in different folders, old backups, or synced accounts. Save a copy of the original VCF file in another folder before fixing it so you can restore it if anything looks wrong.
If it is a small file, you can open the contacts in Outlook or Gmail, merge repeated contacts manually and export a fresh VCF again. But if the VCF has lot of duplicate contacts then manual cleanup becomes risky as one may miss the phone numbers, email IDs, photos or address fields.
For this kind of Outlook vCard cleanup, I would suggest checking Softaken vCard Duplicate Remover. This trusted tool can load Outlook created VCF files, find duplicate contacts and remove them without changing saved contact details like name, email, phone number, address, images and URLs. It also lets you save the cleaned VCF at your chosen location.
Run the free version first on a copied VCF file and check the duplicate results before saving the final cleaned contact file.
