"Use the vendor email address" stopped working

[EvanGR]

The last few days, out of the blue, the vendor of the shop is not receiving email updates on orders.

The option "Use vendor email address" is checked, and there is an additional email in the "Additional vendor email addresses". None receive emails on order status update, and there's no errors reported.

It used to work fine until a couple of days ago.

If I uncheck "Use vendor email address", the emails are sent to the users that are set to receive system emails. Which is a good workaround.

Virtuemart has no problem with sending emails.

Something is changed or corrupted somewhere. Anybody have any suggestion what to check next?

Thanks!

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