The preview functionality in Outlook 2007 is very useful. Unfortunately, you cannot preview any PDFs with it straight ouf ot the box. There is now an unofficial PDF previewer available for it. It works with Outlook 2007 under Windows XP and Vista. I have been using it for some time now and it is very useful!

Outlook 2007 has performance problems with large PST and OST files (>1 GB). Microsoft published a patch today to address those issues. The official description of the patch reads:
“This update fixes a problem in which a calendar item that is marked as private is opened if it is found by using the Search Desktop feature. The update also fixes performance issues that occur when you work with items in a large .pst file or .ost file.”

I had been suffering from this performance problem. After installing the patch, my Outlook 2007 became a lot faster though. If you are having performance issues, you should definitely download and install this patch.

Download the patch

Read the Knowledge Base article

Update: Outlook Team blog post given specifics on the changes this update makes

Outlook 2007 comes with improved IMAP support. As you might wonder what is new, here is the full list of improvements:

1. Outlook is now IMAP4 Revision 1 compatible (RFC 3501)
2. In previous versions, Outlook would pop up a dialog while synchronizing with an IMAP server. In 2007, Outlook uses a new chunking synchronizing strategy that allows users to work with IMAP items as they are being downloaded.
3. 2007 has better purging support. In 2003, you were only able to purge the current IMAP folder, now you can using Edit, Purge:
   • Purge current folder
   • Purge all folders for one IMAP account
   • Purge all folder in all IMAP accounts
   • Use the new Purge on Switch feature that purges items automatically when switching folders. This feature is disabled by default. You need to switch it on for each IMAP account separately via Edit, Purge, Purge Options, “Purge items when switching folders while online”. You can access the same dialog via Tools, Account Settings, Change for your IMAP account, More Settings.
4. You can now store your Sent Items in an IMAP folder. In previous versions, Outlook stored all sent items in a local PST and not on the IMAP server. When you send an email for an IMAP account the first time, Outlook will ask you whether to store the item in a folder on the server or not. You can access the setting at any point in time via Tools, Account Settings, Change for your IMAP account, More Settings, Folders. Please note that this setting will only be available after Outlook has synchronized with your IMAP account once (it needs to download the folder list first from the IMAP account)
5. IMAP accounts now use the Unicode PST format (introduced first in Outlook 2003) by default. In previous versions, IMAP accounts were limited to ANSI PSTs, which meant e.g. that your IMAP account could never be bigger than 2 GB. With providers already offering 2 GB IMAP accounts currently, e.g. as 1&1 does, it won’t be before long that larger than 2 GB IMAP accounts will be available widely. You should know though, that Outlook has no mechanism to convert an ANSI to a Unicode PST. The only way to “convert” your current IMAP ANSI PST to Unicode is to delete the file and let Outlook recreate it as Unicode PST. When you upgrade from an earlier version of Outlook, 2007 asks you whether it should do just that.
6. IMAP logging has also been improved in 2007. Outlook log files are created in “%temp%\outlook logging” and are named according to the account, activity (incoming/outgoing), as well as date and time of the first log entry. Outlook creates one log for each account per session. You can switch on logging via Tools, Options, Other, Advanced Options, “Enable logging (troubleshooting)”.
7. Outlook accounts now have a “Test Account Settings” button. You can find the button on the page where you enter the basic account information.
8. Security for IMAP accounts has been improved as well:
   • TLS encryption is now supported in addition to SSL (as required by IMAP4 Rev. 1).
   • The PLAIN authentication mechanism is now also supported. Meaning the PLAIN SASL mechanism (i.e. AUTH=PLAIN) as defined in RFC 2595 (again required by IMAP4 Rev. 1).
   • Support for STARTTLS was added (defined in RFC 2595). This allows starting SSL for an established IMAP4 session (another IMAP4 Rev. 1 requirement)
   • As for all other Internet E-mail accounts, the private ID field on SMTP outgoing messages as added. This is in reference to the new Postmark feature in 2007. More information about this feature is available on Office Online.
9. IMAP accounts (with the local PST in the Unicode format) now allow Search Folders similar to Search Folders that were already possible on regular PSTs in Outlook 2003.
10. In Outlook 2003, IMAP items could be assigned multiple different flags similar to any other email item in Outlook. This has been changed in 2007to only allow IMAP items to have a flag or no flag (flag can only be on or off). The change was made, as IMAP accounts only support such a limited flagging behavior and the different flags assigned to items in Outlook 2003 were not reflected on the IMAP server. In addition, IMAP items in Outlook 2007 cannot be assigned the new color categories, as those are not supported by the IMAP protocol either.
11. It is now easier to cache your IMAP items locally and even keep a full local copy of your IMAP account in the IMAP PST. In 2003, you had to select each folder individually that you wanted to be kept cached locally in the Send/Receive Settings dialog. In 2007, you can now choose to download all headers for all subscribed IMAP folders (meaning the ones shown to you in the folder list in Outlook) or all complete items including attachments for all subscribed folders. In addition, you can still define a custom behavior. The setting is available via Tools, Send/Receive, Send/Receive Settings, Define Send/Receive Groups, Edit for the send/receive group. Then select your IMAP account and choose the desired setting under “Receive mail items”.

As diagnosed correctly by FeedBurner, the problem of Outlook 2007 not being counted in the RSS subscription statistics lays with Outlook. Michael Affronti, the Outlook Program Manager responsible for the RSS feature, just announced that Outlook 2007 doesn’t and won’t report a custom user-agent string. That means, any service, not just FeedBurner, trying to interpret the data will only see requests from IE7 that look like someone is browsing a feed. Without a custom user-agent string, there is simply no way to differentiate real IE7 feed browsing from an Outlook 2007 feed subscription.

This is extremely unfortunate and with Outlook 2007 probably going to be adopted widely, means that RSS feed subscription statistics will be significantly lower than their real number. How much lower? I can only guess.

FeedBurner reported that I had 148 subscribers and 2445 hits from IE7 on Monday. It seems to me most likely that the majority of those IE7 hits are generated by Outlook 2007. After all, most people would not browse to my RSS feed, but rather browse to my website. Let’s be conservative though and assume that only 80% of the hits (=1956) are generated by Outlook 2007. I don’t know how often Outlook pulls my feed, but once every hour sounds reasonable. If I am very conservative again, I assume that a copy of Outlook pulling my feed is running 24 hrs. In that case, the 1956 hits represent 81.5 subscribers. Looking at my weekend drop though, I would say it is reasonable to assume that most people read my blog at work or at least during office hours. So maybe they don’t have Outlook running 24 hrs, but just 16 hrs. That would represent 122.25 subscribers.

I get to pick then between my total subscription number being 229 or 270 instead of the reported 148.

Quick Links

• Word 2007 HTML and CSS Rendering Capabilities in Outlook 2007 (Part 1 of 2)
• Word 2007 HTML and CSS Rendering Capabilities in Outlook 2007 (Part 2 of 2)

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Outlook 2007 is full of new things. Some of them are very obvious, some of them are predominantly “under the hood” and can be easily overlooked by users. A good example for the latter one are many of the IMAP improvements in 2007, which I will discuss in an upcoming blog post. One of the very obvious changes though is the new email editor for Outlook. Gone is the native Outlook editor that didn’t even have the ability to show you spelling errors as you typed (those red squiggles). Gone are also the days when you could use Word as your email editor. In Outlook 2007, you get one built-in editor, that ’s it.And that built-in editor is Word. Well…not really. The Office teams realized that there was no point in maintaining two editors for plain text, HTML and Rich Text: one simple one (Outlook built-in) and one very powerful one (Word). Therefore they decided to not develop the Outlook built-in editor any further, but to use Word for 2007. However, the existing Word integration wasn’t really a great solution either. It required that Word is installed and it seemed to me that it took forever to load Word whenever I wanted to write an email. Therefore, Microsoft packaged a stripped-down version of Word 2007 into a DLL that ships with Outlook 2007. This means, Word 2007 is not required for the Outlook editor to work. With this approach, a user doesn’t even notice that a reduced version of Word is used for writing emails, but the user notices that the editor is significantly better than the 2003 built-in one (e.g. it has those red squiggles).By integrating Word in this way into Outlook, Outlook also is able to use the text and HTML rendering capabilities of Word. This means that all emails, RSS posts and other email-like items are displayed using this special Word DLL. Internet Explorer is hence no longer used by Outlook to display HTML content. This change alone increases email security in Outlook immensely. To further increase security and do as much as only possible to prevent Outlook from becoming a security risk to a user, WordMail supports a specifically designed subset of HTML and CSS. Any HTML or CSS that could be potentially lead to an exploit, is simply not supported at all by Outlook. Naturally, some of the HTML and CSS features that are not supported by Outlook 2007 made that list not due to security features, but due to Microsoft not being able to implement all of them (lots of browsers, e.g. very notably IE6, don’t support HTML and CSS to the full extent either).

This brings me to the actual topic of this post. As Outlook only supports a specific subset of HTML and CSS only, many HTML newsletters and emails will no display as intended in Outlook 2007. Some of the features not supported are:

• Animated GIFs
• HTML forms
• Applets
• Macromedia Flash
• HTML Frames
• CSS floats

Microsoft has published an MSDN Article detailing the HTML and CSS rendering capabilities in Outlook 2007.

In addition, and almost more importantly, Microsoft has made available a validator tool that can determine whether an existing HTML document uses unsupported elements or not. The validator tool can be used with Visual Studio 2005, SharePoint Designer 2007, Expression Web, Dreamweaver MX 2004 or Dreamweaver 8. A second MSDN article provides walk-throughs for using the tool with these programs and also has the link for downloading the tool.

Outlook 2007 will be released soon (=within the next several months). Now is the best time to take a look at all your HTML newsletters and emails and ensure that they will render great in Outlook 2007.

Update: Joe Hardy did a great job pointing out the real sore spots in the HTML/CSS capabilities of Outlook 2007.