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I'm using the Auction module now. The Auction works fine, but there are no emails sent to users when they place a bid. When you insert your bid
Unable to send e-mail. Contact the site administrator if the problem persists.
When I create an account, then i get a email with instructions. Only by the Auction module the mails will not sent. I saw one topic:
But there was no good answer for me. I used this module auction