Why Do Free Online vCard to PST Tools Fail with Large Contact Lists?

[THOMPSON01]

I recently tried converting a large number of vCard (VCF) files—around 1000 contacts—into PST format using some free online tools. Unfortunately, most of them either crashed, skipped contacts, or produced corrupted PST files. Has anyone else faced this issue? Why do free online vCard to PST converters struggle with large contact lists? Is it due to file size limitations, server timeouts, or a lack of proper formatting support? Can someone recommend a reliable desktop-based utility that can handle large batches of VCF files without data loss or performance issues? I am looking for something that supports bulk conversion, preserves contact details accurately (including photos, emails, phone numbers, etc.), and works well with Outlook 2016 and above.

 

[Levibill_22]

Free online vCard to PST converters often fail when converting bulk contacts, as they are not built for massive or structured data. Fields are missing, formats are corrupted, all they may not support all versions of vCard or Outlook. Moreover, they are dependent on the internet for full upload, risking your contact privacy. I tested the WholeClear VCF to PST Converter with over 7000 contacts and while it worked offline, and kept every detail (name, number, email, notes, images), it also didn't lag. It supports all editions of Outlook (2010-2021); and all vCard formats (2.1, 3.0, 4.0). It's fast, clean and offers a free demo. If you care about data accuracy and time.