Essential WhatsApp files are missing Troubleshoot in iOS

[ebulku]

What are some ways to troubleshoot the error: Essential WhatsApp files are missing from the iOS backup. Perhapse you enabled end-to-end encryption for the backup?

I have checked all the issues related to that error and there are two cases:
a. You have enabled e2e encryption inside WhatsApp Settings > Backup #125
b. You have a Business Account and you are not using the --business flag #164

I have successfully exportet the chats from my iOS 18.3 iPhone, but it is failing in another one with iOS 26.1. (logs in the end)

Since the backup of iPhone is more than 200GB, it is a bit hard to troubleshoot with different cases, so can somebody help with these questions:

1. Do you have to make at least one backup from WhatsApp Settings > Chat backup so Whatsapp-Chat-Exporter can work?
2. Do you have to enable/disable WhatsApp inside IPhone Settings > iCloud Backup, or that is not related at all with the backup you are doing it in your PC though iTunes

Encryption detected on the backup!
Enter the password for the backup:
Trying to decrypt the iOS backup...Done
Decrypting WhatsApp database...WARN: decrypted 543297536 bytes of '7c7fba66680ef796b916b067077cc246adacf01d', expected 714215424 bytes!
Essential WhatsApp files are missing from the iOS backup. Perhapse you enabled end-to-end encryption for the backup? See https://wts.knugi.dev/docs.html?dest=iose2e

[KnugiHK]

I have successfully exportet the chats from my iOS 18.3 iPhone, but it is failing in another one with iOS 26.1. (logs in the end)

If E2E encryption and the Business flag aren't the issue, this is likely a version-specific change in iOS. It's possible Apple has introduced a new mechanism to protect or store these files in your specific version. I cannot verify this currently as I don't have an iPhone running that version to perform the necessary analysis.

Do you have to make at least one backup from WhatsApp Settings > Chat backup so Whatsapp-Chat-Exporter can work?
Do you have to enable/disable WhatsApp inside IPhone Settings > iCloud Backup, or that is not related at all with the backup you are doing it in your PC though iTunes

No, the tool extracts data directly from the internal WhatsApp databases found in the iPhone backup. It does not rely on, or interact with, the 'Chat Backup' feature within the WhatsApp app itself.