When the Windows 8 Consumer Preview landed at the end of February, the Metro-style e-mail client seemed like one of the strongest tools among a sparse and limited set of applications.

Microsoft shipped a few apps to show off the transport-inspired Metro interface that will dominate the next generation of Windows PCs and tablets—but cautioned that none of them were really ready for daily use. The simplified interface of the Windows 8 e-mail client seemed promising, like the shell of an application that could become very good if given the proper care.

With the right improvements, it might eventually end up as a good option for tablet users, comparable to the mail client in Apple's iPad. But Windows 8 is for both tablets and desktops—and the latest version of the Metro mail client is not close to being ready for desktop power users. Whether used on a tablet or desktop, we think Metro Mail in its current form will have users pining for a real desktop application.

Unfortunately, Windows 8 Mail just didn't improve much between February when the Consumer Preview came out and in late May when the more advanced Windows 8 Release Preview shipped. We are less than one month from the final version of Windows 8 being released to manufacturing, with actual Windows 8 devices set to go on sale in late October. The e-mail client will continue to improve, but what's in the Release Preview isn't likely to differ dramatically from what ships with Windows 8's retail edition. So it's time to give the client a more critical look than we did in its first go-round.

Because they are frequently bought by consumers but used for work, tablets are expected to provide a built-in e-mail client for accessing both business and personal messages. Microsoft is obliging by putting Exchange support in the Mail client for Windows 8, but has put itself in a bit of a difficult position. Windows 8, Microsoft says, will provide all of a consumer's or professional's tablet and PC needs, in both touchscreen and keyboard-and-mouse modes. But if the Mail client Microsoft provides free to tablet users works just as well in PC scenarios, it's one less reason to buy the pricey Microsoft Office and its included Outlook mail client.

Microsoft's competition is Apple... and also Microsoft

For the basics of reading and replying to e-mail, displaying folders, moving messages between folders, sending and receiving attachments, and such, Metro Mail works well enough. The interface is definitely optimized for touchscreens, much like the mail clients on the iPad and Android tablets. For mouse-and-keyboard users, the Metro Mail client exceeds the equivalent program for Windows 7 in some respects, but lags behind in overall functionality. Neither one ends up being an ideal option for desktop users.

Windows 7 doesn’t come with a mail client pre-installed as Windows 8 does. Users who want a free e-mail application for connecting to webmail accounts can download the desktop program Windows Live Mail.

Live Mail offers an interface that's similar to Outlook, but has its problems, such as only supporting IMAP and POP servers. Windows 8 Mail improves on this by adding support for Exchange, but takes a step back by dropping IMAP and POP (which rules out connections to Yahoo webmail), at least in the pre-release version. (IMAP support is promised for a later, unspecified date.)

The Windows 8 Mail client also drops the calendar integration found in Windows Live Mail, another decrease in functionality. The overall experience is harmed as the client just seems to be missing random features, like the ability to flag a message for followup. An option to mark messages as junk or spam also seems to be missing (although you can manually move a message to the junk folder).

On the message flagging issue, a Microsoft representative pointed out to us that you could set up a folder to file important e-mails away, but said flagging isn't possible in the Release Preview. Microsoft couldn't say if it will be addressed by the time Windows 8 is released to manufacturing.

A Metro-esque version of Outlook is known to be in the works, but while businesses typically buy Office for their employees, home users are a lot less likely to make the purchase on their own.

As Windows 8 tablets will inevitably be compared to the iPad, it would help if Microsoft could exceed the iPad's mail app in functionality. That hasn't happened yet. While the iPad mail client doesn't offer major integrations with the calendar, the iPad pushes meeting requests and alerts to the user no matter which app they are in, and the user can respond without leaving the current app, making the lack of integration much less problematic.

Also, the iPad can flag messages. Here's proof:

(Clarification: The above screenshot comes from a jailbroken iPad running Mail Enhancer Pro from Cydia. But even with a non-jailbroken iPad, you can flag a message by clicking "Mark" and then "Flag," and the flag will be visible in your iPad inbox and propagate to other clients, like Outlook. The forthcoming iOS 6 is adding a viewing option letting you see all your flagged messages at once.)

It would probably be easier to list the e-mail clients that don't support flagging messages for followup than the ones that do. But for the purposes of this article, we must note that the Windows Phone e-mail client supports flagging. Windows Phone also supports IMAP, POP, and Exchange Active Sync. In these respects, Windows 8 Mail is feature-deficient compared not just to other desktop and tablet apps—it's behind Microsoft's own phone platform.

The Release Preview has also led to users reporting frustration over the Mail client being unable to connect to servers using self-signed certificates. This could be a problem for businesses that issue their own private certificates, or even individuals who host their own mail servers.

UPDATE: One reader asked if Windows 8 Mail lets you view your inbox while composing a new message or replying to a message. The answer seems to be no—composing a new e-mail brings up a window that covers the rest of the application.

This limitation is also true of the iPad e-mail client. Unlike the iPad, Windows 8 does let you view the windows of multiple apps side-by-side (so you could have Mail and a word processor or browser viewable at the same time, for instance). But compared to most desktop programs, the inability to compose e-mail while viewing your messages list is one less option for multi-tasking.

Windows Live Mail not quite dead yet

Given the limits in functionality in Metro Mail and the fact that the Windows Live brand is being de-emphasized by Microsoft, we wondered if the Live Mail client would remain an option for Windows 8 users. At first, Microsoft told us simply that Live Mail will continue to work on Windows 8, without specifying whether that only applies to users who upgrade from Windows 7 to Windows 8 and transfer their applications.

More important is whether Microsoft will continue to make Windows Live Mail available as a free download, and will continue updating and supporting the application for users of Windows 8 and earlier versions of the OS. With a little more prodding, Microsoft gave us some good news: "Windows Live Mail will continue to be offered as a free download to customers of Windows 7 and Windows 8," the Microsoft representative said.

It should be noted that while Live Mail will work on Intel-based Windows 8 devices, it won't work on ARM tablets, which use a special version of Windows 8, called Windows RT, that excludes traditional desktop applications. Major updates to Windows Live Mail probably aren't to be expected. Microsoft certainly wants to sell customers on the Metro mail client—if something as important as e-mail can be converted to Metro on the desktop, it’ll be that much easier to convince users of Metro’s overall utility in traditional keyboard and mouse scenarios.

It wouldn't really be fair to compare Metro Mail to Microsoft Outlook, as that's a professional (and pricey) e-mail client that should (and does) outstrip the capabilities of any free program. But it makes sense to compare the Metro e-mail client to Microsoft's own Windows Live Mail.

In setting up e-mail accounts, Windows 8 Mail takes one step forward and another back compared to Windows Live Mail. For the types of accounts Windows 8 Mail supports (namely, Exchange, Gmail, and Hotmail), the auto-discovery works like a charm. Connecting to your employer's Exchange Server and accounts like Hotmail and Gmail can be done just by entering a username and password. Windows 8 Mail supports Hotmail and Gmail through Exchange Active Sync. But as we noted earlier, it doesn't yet support POP or IMAP, meaning you can't connect to Yahoo Mail or other services that don't support Exchange Active Sync.

On the plus side, the initial step of connecting to e-mail accounts is a lot easier in Windows 8 Mail than in Windows Live Mail (provided you don't need IMAP or POP). I found the auto-discovery process in setting up my Yahoo Mail account didn't work in Windows Live Mail, forcing me to manually enter the IMAP server settings. Since Live Mail doesn't offer Exchange support, I also had to manually configure the client to point to my employer's IMAP server.

I’ve been testing the Windows 8 Mail client in a virtual machine. I tried replicating Windows 8 touchscreen functionality by streaming the VM to an iPad with the Splashtop streamer. Unfortunately, that didn’t provide good enough functionality to make a verdict on the app’s touch capabilities.

Ars IT Editor Sean Gallagher is using Windows 8 on a Samsung tablet PC, however, and says the Mail client works well enough on a touchscreen.

"The wide-openness makes it much better for touch than on a keyboard. It's meant for quick access to mail, and touch replies, not to be a full client," Gallagher notes. "It works. But if you work in Desktop all the time (which most PC users will), it's kind of a drag to use."