It sounds like some permission problem on the site server.
Please try to download the sync file from your Virusdie account or from one of the sites that are already connected.
thank you for your reply. I’ve added it manually but I still can’t add it to virusdie via the MainWP Dashboard. It seems that MainWP is trying to add the file again. The same message “Unique sync file could not be uploaded. Please upload it manually.” appears.
Hey just a quick update: If I click on “Reload Virusdie Data” on my dashboard settings I’m getting the following error: API could not be connected. Please try again or contact support.
It sounds like the Virusdie API server returns invalid data.
Can you try to Sign Out from the VD account in the extension and then try to Sign Up again with the email address that you already used to sign up earlier, so you get the new One-Time Password and Sign In.