Outlook

Outlook 2016 Secondary Mailbox Cached Mode

After migrating to Outlook 2016 from 2010, I noticed this inconsistency.

If you use secondary mailboxes in Outlook, you’re probably going to want them in Online Mode rather than Cached Mode. With Cached Mode on, you’ll have an OST file created for each extra mailbox you add, and you’ll hit performance issues if you have over 500 folders over all mailboxes added to the account.

One of the ways to avoid these performance issues is turning off ‘Download shared folders’ in the mailbox settings:

‘Download shared folders’ disabled

This can be done manually, or company wide with the Group Policy setting “Disable shared mail folder caching” found in User Configuration / Administrative Templates / Microsoft Outlook 2016 / Outlook Options / Delegates. Enabling this will disable and grey out the option as per the screenshot above.

However, I was previously doing this through a registry setting ‘CacheOthersMail’ under HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\outlook\cached mode with the value set to 0. This worked on Outlook 2010 fine I believe, but in 2016 it did something slightly strange. Although clicking on a secondary mailbox’s folders showed they were in Online Mode with the status bar status of ‘Online’, the ‘Download shared folders’ tickbox was still enabled. I’ve confirmed this on both CTR and MSI versions of Office 2016.

At first I thought nothing of this, as it seemed to be working as intended. However, after a while I worked out that having it configured this way lead to performance issues, and people who had over 500 folders had cases where the inbox would stop updating. Changing the tickbox setting resolved the issue, despite the secondary mailboxes before and after this showing as ‘Online’. I didn’t dig into this any further so I can’t explain what was actually going on, but at a guess it was still doing some sort of sync or connection on each folder despite it being in Online Mode.

My advice is – make sure the ‘Download shared folders’ tickbox is off rather than just checking that the folders show as being ‘Online’. If you really need a secondary mailbox in cached mode but want to disable it by default, you could add it as a seperate mailbox account which will have it’s own cached mode settings.

 

 

Outlook 2013 & 2016 Blank Screens and Crashing

Since going from Outlook 2010 to 2016, I’ve noticed several issues. They’re outlined on this TechNet article which lists:

  • Buttons on the Outlook ribbon failing to paint properly
  • Email messages displaying either blank or black in the Reading Pane
  • The Navigation Pane failing to draw all folders properly
  • Various rectangles appearing in the Outlook user interface (UI)

There’s also just Outlook crashing/freezing/running slow. This has been an ongoing problem, and I suspected 3rd party addins to be the culprits. That’s sort of true, however it turns out it’s an overall memory issue with 32 bit Outlook having ~2GB of RAM to access, shared amongst all the 32 bit apps running on your computer.

If you want to know that low memory is the cause of your issues, one way is to use the Sysinternals VMMap utility and follow these instructions. If your free memory is under 250MB, then you’re working below the requirements of what Outlook needs to have available to continue running smoothly.

The article above is very well written and detailed, with the primary remediation suggestion being to go 64 bit Office. This isn’t a short term realistic solution for many companies who have legacy 32 bit addons, or vendors who just haven’t got there with 64 bit addins yet. It only takes 1 addin for that idea to come crashing down, and then there’s the testing of all the re-written apps, and then deploying out; an uninstall of the whole Office 2013 or 2016 32 bit suite, uninstalling all the addins, deploying Office 64 bit, deploying the new addins… it’s potentially a huge project to take on.

There is hope though for those of us who can’t go 64 bit (again the article has many suggestions), which is a new feature called Large Address Aware (LAA). It doubles the amount of memory (4GB) available to the Office apps. It’s already rolled out to Outlook 2016 build 1709. That makes sense if you’re using the Click to Run (CTR) version of Office 2016, but the MSI version that many still use hasn’t got this update yet. Referring to the TechNet article again on this issue, there’s no exact specific mention that LAA will come to the Click to Run version of Outlook 2016, so we’ll have to wait and see.

If you’re experiencing a less than great experience with Outlook 2013 or 2016, it’s worth understanding the above and seeing if you’re affected. This may drive you to change to Office 2016 CTR, Office 2016 64 bit, or even both – or leave you to work out how you can improve the experience, with potentially disabling Outlook addins that aren’t necessary.

I am trying to work with Microsoft on this issue too, so feel free to ask any questions or make any comments and I’ll see if I can assist.

Stellar Exchange Tookit Review

Stellar Data Recovery reached out to me to see if I was interested in reviewing their product. I only accept these when I can see a personal interest in what the product does. The 5 key things this product does are:

1. Repair corrupt EDB files
2. Mailbox Extractor for Exchange Server
3. OST – PST conversion
4. Mailbox Extractor for Exchange Backup
5. Password Recovery for MS Exchange

Primarily I was interested in OST to PST conversion, as I’ve tried to do this before and had no luck with free solutions, and wanted to try a paid product that could solve the problem. (It’s also worth noting this isn’t cheap software. Also if you only want a more basic OST to PST converter, they sell that by itself for a lot less.)

I tested the Exchange Toolkit on an Outlook 2016 OST file I’d copied off another computer, that was 2GB in size. It does take a little while to process, but displays the results in a nice Outlookesque GUI:

There’s also a search function, which is handy if you’re just after a particular email from the OST.

If you need to export the results, there’s a bunch of useful options:

I was impressed with the options to export directly to Exchange Server and Office 365! But for me, I was happy with a PST. The resulting PST file was readable via Outlook 2016, so the product does exactly what it says on the virtual box.

Another part of the toolkit I looked at, was the Mailbox Extractor. Again, there’s several options, but I tried connecting to a live Exchange 2010 server to extract emails:

After connecting, again I was presented with an Outlook style of emails. I then realised there’s a few use cases for this tool that are handy to me personally; if I need to go into a mailbox to get something out, this is much easier than adding a second mailbox or profile. It also then lets me take out those emails in a variety of ways – for example, I can select a folder and then export all contents of that folder into several formats, such as PST, MSG, PDF, HTML and RTF. For HTML and PDF, it will create a file per email with the same subject name.

I can see the other functions of this product being useful for someone who’s often dealing with other companies’ data, old data that needs to be restored, or extracting out a mailbox from an online Exchange server. It’s an interesting array of tools, and I’ll try to report back on whether this tool does the job well or not.

Worth checking out these tools if you run into a scenario where you need them – sometimes there’s a freeware or open source solution, but often they don’t work, are old, unreliable or limited in functionality. Stellar Exchange Toolkit seems to do what it claims well, and I look forward to trying more features in the future.

Viewing Mbox Files On Windows

A MBOX file is similar to a PST file, in that it contains a collection of emails. PSTs will be familiar to those of us in the Windows world, as it’s one of the old formats Outlook will use.

(Side note: PSTs are bad, but they do function well as a way of transporting a large chunk of mail from one place to another).

MBOX is the Unix version of PSTs. Google also uses this for Gmail, so if you run an export job, you’ll end up with a MBOX file. Microsoft Outlook doesn’t support this format though – so if you’re sent one, how do you view the contents?

If you start Googling, you’ll come across a bunch of ‘free’ viewers and converters. Most of these are free in the demo sense, and will only view or covert 20ish emails.

I eventually found these two free solutions and tested that they worked; if you find any others feel free to share.

 

Windows Mbox Viewer

This is a free, open source viewer of MBOX files. There’s no installer, just launch the exe, open your MBOX file and you’ll get a simple list of emails and can view the contents. Beyond being able to do searches, the program doesn’t do anything else. This is a great, simple solution if you just want to view the contents of the MBOX file. If you have Outlook installed, double clicking on an email will open it in Outlook, which can then be saved/printed.

Thunderbird

This is also completely free, from Mozilla. Here is a great set of instructions on how to configure Thunderbird to be able to read your MBOX file, but there’s a few more steps involved. Once Thunderbird can see them, you have a lot more options. The emails can be synced to another mail server, or you can simply select emails and save them out. They’ll be saved in the EML format, which Outlook will then recognise. More information about importing and exporting is available here.

 

I never found completely free software to convert from MBOX to PST, so if you really need that functionality, it might be time to take out the credit card and pay a hard working developer!

Outlook Cannot Send This Item

Microsoft Outlook has a reasonably common, yet very generic error:

cannotNo Outlook, it was not helpful.

There are a bunch of reasons that can cause this error. Often, the ‘solution’ is to change the email from HTML to Rich Text or Plain Text, and move on. Or, copy/paste the entire email into a new email and move on. Neither of these are workarounds of course.

Dig a bit deeper on the web, and you’ll find some wackier reasons – the size of the logo in your signature for example. There was also a version of Exchange 2010 that caused the issue, but that was resolved.

I was running into this problem on a regular basis, and spent many hours trying to come up with a reason for the issue, and why only certain users had the issue, and on certain emails. I couldn’t reproduce on my own PC with the exact same emails, yet it was 100% reproducible on theirs. Also, if I removed the image from the user’s signature it fixed it – and it didn’t matter what image I put back in, it was always broken.

It wasn’t until I cried out for help on Twitter, and Christopher Kusek came to the rescue. After looking at a few other ideas, he pointed me towards hotfix KB3042197 with the lengthy title “ Graphics file attachment grows larger in the recipient’s email message after you change to a high DPI setting”

After reading this, I did some testing. Amazingly, the problem only occurred when the PC’s DPI setting was above 100%. Amazingly, when DPI is 125%, 150%, 200% etc, Word from inside Outlook resizes images in the HTML code based on your DPI setting. Some combination of HTML emails back and forth, and this resizing would cause the ‘Cannot send this item’ message.

Setting the DPI to 100% wasn’t enough either, as it would make the contents of the screen too small for some users. The registry setting mentioned on the KB article ‘DontUseScreenDpiOnOpen’ and setting the value to 1 (true) actually fixed it!

After some more testing, this single registry setting which you’d think would be on by default was rolled out, and the ‘Cannot send this item’ messages were no longer appearing. At least not for this particular problem!

TLDR: If Windows is set to > 100% DPI, the MS Word editor inside Outlook 2010 and Outlook 2013 will resize images by default and this can cause weird stuff to happen.