When your contacts come from different devices like Android, iPhone and email clients, you usually end up with lots of separate VCF files. Managing them like that becomes messy, and importing each file one by one often creates duplicates or missing contacts. The safer way is to merge all contacts into one single VCF file first so everything stays organized. I had contacts exported from an old Android backup and iCloud and needed them combined before importing into Outlook. Doing it manually wasnt practical and some free online tools changed contact formatting. Using a proper merge tool solved it. Softaken Merge vCard Pro lets you add multiple VCF files from different devices and combine them into one single clean file without touching any contact details. Phone numbers, emails, names everything keeps the same after merging. Once all contacts are in one file, you can import them into any device or email platform easily without confusion or duplicates.