I cannot get access to my Wordpress site.

I need to ask for a little advice. I have just read your latest article on getting access so I thought I would ask the question even though it is not strictly a WPMUDEV problem but a Woo Commerce problem, so the reference to the Dashboard is not strictly correct.

I have been unable to get access to my wordpress site melvichestamps.com either as an admin or a visitor.

When I try I get the following message: "Fatal error: Cannot redeclare class WC_Shipping_Zones in /home1/candj803/public_html/melvichestamps.com/wp-content/plugins/woocommerce/includes/class-wc-shipping-zones.php on line 17"

How can I fix this? Can I use FTP such as filezilla to delete the plugin? or should I attempt to use the backup which I have with "Hostgater" or another back up which I have on dropbox?

I'm not sure how long this has been like this so the backups are not likely to help.

Thanks

John Melville