To delete all iPhone contacts one at a time could literally take all day if like me you have close to a thousand contacts.

To delete all iPhone contacts you will need.

iTunes and an Email client such as Microsoft Outlook

Broad Description
In broad terms we need to create a separate email profile with no contacts, then make this the default profile, then sync your iPhone with iTunes and choose to sync contacts.

Step by Step Guide
From Windows Go to Control Panel – Mail

Show Profiles – Select Add and give it a name such as empty – Now in account setup enter anything – select next – Ok to create a Profile with no e-mail accounts.

You have now created an empty profile

Under Always use this profile choose the profile you have just created.

Delete all iPhone Contats

Launch iTunes – Devices – Info tab – Scroll down to advanced and tick Contacts under Replace information on this iPhone, now hit apply.

iTunes Contacts

This will remove any contacts on your iPhone and sync with the empty Outlook which contains no contacts.

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