Getting Outlook.com to work with email client applications via IMAP is proving to be a challenge for some users of the Microsoft webmail service.
A variety of problems have been reported through comments in the blog post Microsoft published Thursday announcing the new IMAP (Internet Message Access Protocol) support in Outlook.com.
To their credit, Microsoft officials are clearly monitoring the feedback very closely, as evidenced by their frequent replies to the comments being posted.
"We've seen a handful of reports of users running into the error 9 so we're looking into this with high priority," wrote Ben Poon, an Outlook.com program manager with Microsoft, referring to a server timeout error some users are experiencing.
Another common complaint is that messages deleted using IMAP-compliant client applications remain on the Outlook.com Web interface.
The thread of comments, which is now nearing 80, also goes into questions and recommendations about specific configurations under certain scenarios and for particular OSes and email applications.
Matthew Cain, a Gartner analyst, said that scaling up IMAP support, particularly given the various ways IMAP can be interpreted by developers, can be difficult.
"Thorough testing at scale, and testing of all major permutations, is a requirement before any go-live action," Cain said via email.
Microsoft declined to comment on the issues.
In its announcement Thursday, the company said that support for the IMAP email retrieval technology would expand the scope of client software and devices that can interact with Outlook.com.
"With today's announcement, we now have a richer email experience across devices and apps, including those not using EAS (Exchange ActiveSync), such as Mac Mail and Thunderbird on a Mac," wrote Microsoft official Steve Kafka in the blog post.
Outlook.com already worked with EAS, which allows it to be used with devices running the Windows Phone, iOS and Android mobile operating systems, according to Microsoft.
Microsoft was prompted to add IMAP support based on feedback from Outlook.com users who let the company know "loud and clear that this was important," Kafka wrote.
The addition of IMAP also opens the door for third-party developers to create applications for Outlook.com or integrate existing applications with it.
Microsoft detailed in its blog post how several developers have already linked their applications and Web services with Outlook.com using IMAP.
One of them is TripIt, which can now detect emails with travel confirmations in Outlook.com inboxes and import them into a TripIt itinerary.
Outlook.com, first unveiled in mid-2012, has replaced Hotmail as the company's webmail service. Microsoft describes Outlook.com as a total reinvention of webmail, from the user interface to the back-end platform. With Outlook.com, Microsoft expects to have a stronger competitor to Gmail and Yahoo Mail.
However, Outlook.com has been hampered by occasional technical problems, including an incident last month in which the product malfunctioned in various ways for several days, as well as a prolonged outage in March.
Juan Carlos Perez covers enterprise communication/collaboration suites, operating systems, browsers and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.