It seems there is a wide issue affecting the synching of Windows Live email to Windows Phones, with a 5 page thread in Microsoft Answers attesting to the number of users affected.
The issue appears to be that contacts from Windows Live would sync, but the contents of the Windows Live email inbox will disappear on the Windows Phone, but not on the website, and dates to the introduction of Outlook.com.
Whatever the reason, the solution, volunteered by Emily Kao Messmer appears to be to delete Twitter from your accounts associated with Windows Live on your phone, reboot your phone and watch your mail pour in. Adding back twitter afterwards does not appear to be an issue.
Are any of our readers experiencing this issue, and did the solution help? Let us know below.
Thanks Edward for the tip.