When I got my new laptop a few weeks ago I thought it was pretty cool that it came with Office 2007. The nifty new toolbars and embedded wavey swooshes are slick. I don’t really mind that by default Word and Excel assume you want to save files with a .docx or .xlsx extension. (That’s fine with me; makes it easier to remember to not save something as an ’07 file if I need to share it with others that are still using Office XP or 2003.)

What I cannot handle is the fact that Outlook 2007 is using over 130 MB of RAM. 130 MB?! I wouldn’t mind that much, since apparently it’s supposed to play nicely with Windows and just use whatever RAM is available. But even using as much memory as it is it’s still slow slow slow. And this is even after I disabled iTunes 7.3’s ridiculous Outlook add-in. 130 MB?! Are they crazy?

There are 32 comments on this post

  1. Hey namesake,

    you might also consider that this is 2007 and you should have 1-2GB of ram by now. 130MB isn’t so bad. If you’re running Vista that alone takes way more.

  2. Microsoft is on a one company mission to keep productivity at a constant or decreasing level in the face of the threat from Moore’s law.

    Excel makes me nostalgic for VisiCalc.

  3. BTW VisiCalc hogs a whopping 27,520 bytes, that’s less than 1/4 the size of the image at the top of this page.

  4. Outlook 2007 is atrocious. It’s horrible. I cannot imagine how M$ could release a product that works so amazingly poorly.

    It takes forever to compose an email because the ENTIRE OS locks up constantly whenever Outlook2007 is maximized. The *only* way to use Firefox — or any other app, really — is to first exit Outlook. It’s unbearable and inexcusable.

  5. 130MB??? Hah!! I’d be happy if it were only 130. I’m sitting here right now looking at mine that’s over 500MB…

  6. My mail.app on my mac takes around 370MB… but I have 3 large email boxes… one exchange and two imap.

  7. dude, my outlook 2003 is consuming 350-500Mb and takes my 2Gb Ram machine completely down. What is amazing is that no one has yet deliver a proper email client to replace outlook once and for all. all the alternatives have problems, either they don’t do calendar, or they suck at email or or or. Outlook is the king of the desktop, there is no business pc out there that does not spend the full day with outlook open and the software is a piece of crap. for god sake, somebody help us, give me an alternative and I’ll go for it.

    I have around 40Gb of email that I keep around for searching and so on…

  8. If you can trim down your email boxes it will help a lot. I was importing GMail into my mac mail, which included the MASSIVE spam folder. I deleted the spam and it dropped the memory usage down to 52MB.

  9. Well, I now have around 20 pst files to keep them small. But Outlook is just a pain… I wish I could replace it with a proper business tool. Not enough importance is being given in the market to this tool… it owns the desktop and there are no alternatives.

  10. Anonymous Coward

    Outlook does not own the desktop. There are plenty of groupware apps out there. And yes, outlook 2007 seems to load emails into memory, so your usage is pretty much a direct relationship to your mailbox size.

  11. Anonymous Coward

    BTW if all you care about is email, then scrap the groupware category altogether and go with a simple mail client, such as Outlook Express (since it comes with XP – called Windows Mail on Vista), or countless others. I hate groupware like Outlook, Lotus Notes. Software should do one thing well, not lots of things terribly.

  12. stumbled upon your blog… google seach words: “outlook memory hog”. My outlook 2007 has gotten so slow it drives me crazy. It’s using 222megs of memory. If I leave it open… the longer it’s open, the more memory it will consume throughout the day. It’s just flat out stupid. As for an alternative… thunderbird has a nice calendar addon, with task. It can also sync with a gmail calendar if you need it on the go. (outlook can do that too).

  13. Mine’s sat here using 330Mb – bring on the trumpets

  14. Well, I’m looking at Windows Task Manager and Outlook 2007 is currently consuming 164MB of memory and I shut it down about 10 minutes ago!

  15. Yeah..well I have ED, so how’s this suppost to help me out?

  16. ED as in Erectile Dysfunction? Sorry, outlook can’t help you with that 🙂

  17. This is a “feature” of Windows called “Advanced Memory Allocation”. Basically, when Outlook boots up, the image (the executable) consumes ~20MB, but as it runs, if there’s RAM available, it’ll consume it. Windows works to monitor the additional RAM used, and when it gets a request for RAM from another program, it reallocates the memory away from Outlook. If you want to see it in action, bring up Outlook and click around a bit, then bring up your task manager. Find “OUTLOOK.exe” in the image name column, and note the Mem Usage (on mine ~96MB). Now minimize outlook and note the majority of the RAM has been freed up for other programs and Outlook now consumes <10MB (~6.5MB on mine). I’ve never seen a program other than the Office suite or IE behave this way, so I’m guessing it’s an “undocumented feature”.

    This being said, this functionality must have a leak in it. If you run your PC for a week without rebooting, try the above process again. You’ll find you don’t get so much RAM back…


  18. Found your blog on Google in reply to “why does outlook use so much memory”.

    I use XP Pro & Office 2007 with 2Gb of RAM & 100+Gb of free hard disk & still get “insufficient resources” messages. Minimising the Office 2007 windows seems to work, but I agree with the earlier comments – Microsoft ARE crazy & on a mission to negate Moore’s law!

  19. Just a quick note – same problem.

    Specially the random freezing – hugely irritating.

    But I just went into options and disabled “check if people are online” or whatever it is, and that seems to have made it feel a lot more responsive.

  20. When you guys refer to memory I bet you are NOT referring to the “working set” memory. The working set memory is not the default memory display in task manager (I forget which one was the default). The default one reads much lower than the “real” memory used. Another one of Microsoft’s bright ideas to not show the real extent of the issue! And of course my Outlook uses way too much memory. One suggestion, try installing service pack 2 – it seemed to help just a tiny bit.

  21. Wow this is the I hate MS blog. We in a corporate environment use outlook 2003 and 2007 effectively and efficiently on machines ranging from 512MB dell GX260’s to powerhouses with 4GB of ram. Nobody (even the guys with huge mailboxes) ever has an issue with getting their work done. Maybe its the open source porn downloads your having an issue with? OMG MOMMY !!! THE BAD MS GUYS ARE USING MY MEMORY CAN YOU BUY ME MORE PLEASE !!

    I was just looking for memory usage to calculate how much memory we’d need for a citrix setup. Good luck with umm your issues. (FYI I have a online mailbox with about 100k messages totalling about 7GB) not a blip (only 2GB machine running vista)… sigh.

  22. K, seriously? What a lame response. We’re in a corporate environment too, and we see some of the same issues on some desktops, but not all. It’s not open source or porn downloads. It does seem to correlate to add-ins, size of the mailboxes, and contact presence detection. Still, the admins that immediately jump to ‘you must be downloading porn’ give IT a bad name as an unresponsive and uncaring group. Try helping if you’re going to post…. I hope you treat your users better than that.

  23. K, you’re such a donkey….

    “We in a corporate environment”, like if the rest of us are masturbating at home… Is this your first job and you thrilled about having one or what???

    Do you think people in the “masturbating environment” generate 20GB of PST files?

  24. As a small business owner (not in a corporate environment) I initally found Outlook 07 to be a hog as well. But after a few settings modifications it works perfectly now. The first was the Search Indexing. I use Windows Search 4.0 which by default searches my outlook. In turn I disabled the Outlook search and that made a huge difference in Performance. Also you might consider disablable any Third-party add-ins you dont’ use and the to-do bar. Just thoughts!

  25. Actually I found a much better solution: I converted from Windows to Apple and that solved all of my problems with crappy software. I absolutely do not believe that what you are saying is true, Mr. Rubash. No matter how much you may have improved your Outlook experience by tweaking its settings and disabling features and upgrading your operating system, it cannot compare to the wonderful product that is Apple’s standard Mail application.
    I will never purchase another Microsoft product and enthusiastically encourage anyone frustrated with Outlook to consider simply switching to Apple.

  26. Okay, that sounds like it’s was a more suitable solution for you. I was just trying to help. If I had to “purchase software” then I might consider apple as I’ve heard many great things. But since my all my software is free, I’ll make due with what I got. Happy Computing!


  27. mine is using 1gb of memory!!

  28. Hey Folks,

    I’ve seen a lot posts regarding this issue. The solution is quite simple actually. I see here we have some “perect” networks with admins that are obviously way over smart and nothing ever goes wrong. Well, for me and my 1600 user networks, nothing is ever simple and pretty, so kudos to K for living in such a perfect world.

    For the rest of us … Your “outlook profile” is corrupt. Yes, ok, you could spend a lot of time trying to figure out why it broke and also trying to repair the profile .. if you have a lot of time, go for it .. but if you want it fixed .. follow these few simple steps.

    Find your “.PST” files Back them up to a different folder (just to be safe).

    Go to “Control Panel” and find your “MAIL” Control Panel Icon. Open it. You will see 3 buttons (E-Mail accounts, Data Files and Show Profiles). Choose Show Profiles. Here you will 2 areas in the window). In the TOP area, Select “Add…” and create anew profile name. When it’s created, it will prompt you to build your Outlook account. Please input your outlook email account information here. When this is finished. Change the 2nd area to “Always use This Profile” to your newly created profile.

    If you use Exchange in cache mode, your current email will auto-update per whats in your email box on exchange. If you are using PSt files, you can import your data from your prior pst file (we made a copy before you started this process). If you’re using PST files .. Run ScanPST first ebfore importing. There is no reason you can’t spend 3-5 minutes ensuring your file is ok before importing.

    Good luck and I hope this has helped some of you. I know that some just can’t be helped and I can live with that 🙂

    Good Day

  29. Steve,

    how about your solution if my OLK 2007 (SP2) is consuming 1GB of RAM before even asking which profile to use?
    I’m on a T61 running Vista Ultimate SP2 and 2GB of RAM. And no other app running in parallel. Also, just 3 POP3 mailboxes and a single 100MB PSt file…


    Another Steve 🙂

  30. Have you tried opening in Safe mode to see what the issues are?

    outlook.exe /safe Starts Outlook without Microsoft Exchange Client Extensions (ECE), the Reading Pane, or toolbar customizations. Component Object Model (COM) add-ins are turned off.
    outlook.exe /safe:1 Starts Outlook with the Reading Pane off.
    outlook.exe /safe:3 Starts Outlook with Microsoft Exchange Client Extensions (ECE) turned off, but listed in the Add-In Manager. Component Object Model (COM) add-ins are turned off.
    outlook.exe /safe:4 Starts Outlook without loading outcmd,dat (customized toolbars).

    Also What Add-ins do you have loaded?

  31. I have been using Thunderbird for months now and it is 10 times faster than Outlook, especially the search function. It doesn’t have all the functionality of Outlook though. It imports things from their default locations, but you can’t set where you want to import from. I also can’t figure out how to automatically send certain files to a folder, but I have never been able to make that work in Outlook even though it is supposed to work!

  32. I disabled the business Contact Manager add-in: Trust Center / Add-ins / Manage and went from 10000 handles to 2700, plus memory usage dropped 50MB

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