Confirmed: Yahoo was the source of WP7's phantom data bug

Raafel Rivera of Withinwindows has confirmed that Yahoo’s IMAP server was the root cause for some users heavily exceeding their monthly data transfer limit with Windows Phone 7. Yahoo’s IMAP server responded to a FETCH request with over 25 times the needed data. Microsoft has now also confirmed this, and promised that a fix is coming within a few weeks.

Hit View Post to see the geek-stuff.

A regular Fetch response:

* 1 FETCH (UID 258 BODY[HEADER.FIELDS (MESSAGE-ID)] {81}
Message-Id: [contoso194089-0-1475496219-3-11262342655328369@CONTOSO.COM]
FLAGS (XAOL-RECEIVED XAOL-GOOD XAOL-GOODCHECK-DONE XAOL-CERTIFIED-MAIL XAOL-BILLPAY-MAIL $hasEmbedded))
…
OK FETCH completed

Yahoo’s Fetch response:

X-YMAIL-UMID: 1_1231_AH9SAiosajdifsLGYp8
Delivered-To: rafael@withinwindows.com
Received: by 0.0.0.0 with SMTP id b14cs36932vcd;
Wed, 24 Nov 2010 09:48:20 -0800 (PST)
[snipped]
Received-SPF: pass (google.com: domain of bxp60spbgycisj582h2kt@contoso.com designates 0.0.0.0 as permitted sender) client-ip=0.0.0.0;
DomainKey-Status: good (test mode)
Authentication-Results: mx.contoso.com; spf=pass (contoso.com: domain of bxp60spbgycisj582h2kt@contoso.com designates 0.0.0.0 as permitted sender) smtp.mail=bxp60spbgycisj582h2kt5hjwxuss6f@contoso.com; domainkeys=pass (test mode) header.From=dummy@contoso.com
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
s=200505; d=email.contoso.com;
b=[snipped]+CKirfbuapQiU=;
h=Date:Message-ID:List-Unsubscribe:From:To:Subject:MIME-Version:Reply-To:Content-type;
Date: Wed, 24 Nov 2010 17:48:39 -0000
Message-ID: [bxp60spbgychw1axh2kt.7412145937.3427@MTA915.CONTOSO.COM]
List-Unsubscribe: [mailto:rm-0bxp60spbgychw1axh2kt@EMAIL.CONTOSO.COM]
From: “Contoso” [dummy@EMAIL.CONTOSO.COM]
To: rafael@withinwindows.com
Subject: This is a test message
MIME-Version: 1.0
Reply-To: “Contoso” [dummy@EMAIL.CONTOSO.COM]
Content-type: multipart/alternative; boundary=”=bxp60spbgychw1axh2kt5hjwxuss6f”
…
OK FETCH completed

Tags: phantom data, WP7, WP7 bug

Category: Windows Phone