Acknowledge receipt of every complaint immediately by e-mail. Your first contact should be an e-mail message (or phone call, if the complaint warrants it) letting the customer know that you've received the complaint, that you're sufficiently concerned about the problem to contact the customer, and that your customer service team is working to resolve the issue.
Here is a sample e-mail message you can use to confirm receipt of a customer complaint.
To: Andrea@customer.com From: Jvirtual@acmesports.com Subject: Complaint
Dear Ms. Jones:
We received your complaint, and our customer service team is now looking into the issue. Thank you for bringing this matter to our attention.
Within [identify a time frame that is both short and achievable] we will provide a more substantive response to your problem and a suitable solution.