Very large Outlook PST file

Appleby

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Need some help here guys and gals. I've got a customer who has been complaining that Outlook '07 is super sluggish and keeps saying "not responding" for 10-30 seconds at a time. When she opens an email to full screen and then closes it, Outlook freezes and stops responding nearly every time.

I checked the size of her PST file and it was 6.2 GB! Come to find out she has emails dating back 6-8 years. Thousands of them. Then I noticed she had about 1,000 emails in her Trash and about 800 in her Junk Mail folder. She confirmed that I could delete all those so I did. Closed Outlook and the PST file was now 5.97 GB. She went home and archived and deleted tons of emails. I mean tons. I deleted the Trash again and compacted the PST but it will not go smaller than 5.97 GB.

Any ideas on why it won't shrink any further and what I can do?
 
That's a big file to handle. A HD fragmentation might help, as well as a RAM upgrade. This is of course, assuming that there is nothing wrong with the Outlook installation. You can try backing it up and reinstalling Outlook, however it sounds like it might be a HD thrashing issue due to fragmentation and low memory. Disabling and re-enabling virtual memory may help as well.
 
Thanks for the advice. I considered a defrag but I wasn't sure why the darn PST file size isn't shrinking?

A reinstall of Outlook was already mentioned but this lady is a Christian missionary and the home office of her organization is 3 hours away and they installed Office for her and have the disks and serial number there. They told her that next time she's at the home office they could uninstall/reinstall for her.

The machine is a Toshiba laptop running Vista and I can't remember how many GB of RAM. It's a fairly fast pc (for the little that she does) but that's a huge PST. I was hoping to get it down to 1-2 GB but like I said, the clean up and compacting did nothing?
 
Outlook 2007/2010 can handle PST Files of about 20GB, though even MS recommend you keep it under 16GB. What I ofen do with customers who have large files is to make a new file for each year and transfer that years emails to it. Just keep the main PST for the current year. Having said that i have some customers who refuse this idea and have 12-14GB files in operation, then complain that its "so slow".
 
Thanks so, maybe I should try backing up all her emails (she doesn't have that many left...) and contacts, create the PST, import and see how it goes from there? That would be easy enough and the old PST file would still be in place in case there was a problem. Sounds reasonable.
 
Oh and just another tip, I noticed you said the PST wasnt shrinking. It wont until you compact it ( Why MS did this I have no idea). To do this right click on the personal folder on the right hand list , you need to make sure you are clicking on the actual top of the list, not a folder within. Choose properties, then advanced, then "Compact Now".

Do this only AFTER you have moved/deleted the unwanted emails in the PST file otherwise you will need to do it again. Then just leave it for a long while. I had one of about 2GB in size and it took about 6 hours to compact to 900Mb on an i5 machine. Of course the size you end up with depends on what you have left in the file, but it can shrink many GB if you have moved alot.

It turns out that in outlook when you delete or move mail, it doesnt reorganise the whole PST it just creates a space where the moved or deleted email was. Compacting, does just as it sounds, compacts and removes all the spaces to make the file smaller.

EDIT Sorry just re read the original post where you said you compacted already. I will leave this here for reference, but sorry for jumping to the wrong conclusion.
 
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Ha, glad you noticed the part about compacting, I was thinking I must have left that part out.;)

Oh so I can just degfrag the PST file? I didn't know that! I learn something every day. I'll def. try that in the morning when I get to the office. Thanks!
 
Would it be quicker to export to a .pst file and then import it back in again?

This is starting to head towards the correct approach. I'd skip the export...and just go for a fresh import.

First..clean up the old PST as best you can (seems like this has already been done). Notice it will not shrink simply by doing that..similar to Exchange and the infostore...it won't shrink simply by deleting stuff. Has to be defragged/compacted. Waste of time doing this on a PST..compacting it will only lead to it blowing up down the road.

Once PST is cleaned....rename it. outlookold.pst or something. Create a new PST...launch Outlook...Outlook will cry and whine about not being able to find the PST ...(we expect this because we renamed it)...so point it to the new PST. Once it mounts the new fresh virgin clean empty PST...go to file..import....yada yada...browse to outlookold.pst...and import the data. Once that's done...once you've verified Outlook is running fine...after some time, you can delete that old PST.

You end up with a fresh clean PST, and importing the data from the old one ensured that data comes over clean and error free.

This process is really very simple, and does not take much time, and helps to ensure less problems down the road.
 
Your information is 9 years out of date. :eek:

While yes outdated for any pst created in the past few years. We don't know when the original pst was created, and could very well be using the older format if it has emails saved from 8 years ago. And yes I agree with everyone else, just import into a new pst file.

OST files still maintain a recommended max of 2GB though ;)

Drake
 
W

OST files still maintain a recommended max of 2GB though ;)

Drake

There was an update to Office 2007 that addressed that and you could go much larger after that update.

If you have Office 2007...without all the updates....the "recommended" max OST file size was 2 gigs...it would support it larger than that. However...there was an update post SP1 which more than doubled that "recommended" max size to 5 gigs. And you could go to 20 gigs.
Source:
http://support.microsoft.com/kb/940226


Currently with Outlook 2010, max PST and max OST file sizes are now 50 gigs
http://support.microsoft.com/kb/982577
 
YeOldeStonecat, thanks for the help. I'm doing that as we speak. After further review she did NOT delete near as many emails as she said....well maybe she did, but from what I can tell she has a few thousand.:(

I'm doing the import right now which is taking FOREVER because she has tons of folders. I'm hoping this will solve the problem. If not, I'm telling her to live with it or delete the old emails. I've spent about 3 hours on this, including research and I gave her an estimate of 1 hour.

Oh and for the whole 2 GB or larger debate....I have no idea what the "correct" answer is but I do know this, I've never seen Outlook really handle a PST file bigger than 2-3 GB max. And I'm not talking about old machines, I'm talking Core 2 Duo's with 4+ GB RAM. I'm not saying it's this way every time but I am saying that,from what I've seen, the bigger the PST, the bigger the problems.
 
UPDATE: Ok I think the problem is resolved!

Thanks so much for all the advice. As I mentioned above, I took the advice to just create a new PST file and import the old one to the new one. It took well over an hour but it finally completed and seems to be working great now. The PST file size went from 5.97 GB to 2.5 GB. Huge difference. Now if I can just get this customer to delete her emails and not fill it back up!

Oh and one more thing....for those that ever attempt something like this, as YeOldeStonecat mentioned, if you change the name of the Outlook.pst file, (to something like OutlookOld.pst) Outlook freaks out when you open it and it wants you to go locate Outlook.pst. At that point, I can find NO way to create a new PST file. You are stuck in a loop of "Locate Outlook.pst" or nothing. After 2-3 times of cancelling it closes Outlook. Soooo, the way to combat this is to go back and change OutlookOld.pst to Outlook.pst. Now open Outlook and all is normal. Then go into Data Managment and create a new PST file, close Outlook and go change the file names at that point. Just a heads up, I hope that makes sense...

Thanks again guys.
 
Oh and for the whole 2 GB or larger debate....I have no idea what the "correct" answer is but I do know this, I've never seen Outlook really handle a PST file bigger than 2-3 GB max. And I'm not talking about old machines, I'm talking Core 2 Duo's with 4+ GB RAM. I'm not saying it's this way every time but I am saying that,from what I've seen, the bigger the PST, the bigger the problems.

I see many many of them well into double digits all the time.
Many amateur techs will put them on a server..and have the workstations read them across the network. Not only does Microsoft not support this setup, but I've taken over networks where this was done by the prior wanna-be tech...and they had frequent issues. Frequent corruption, horrible Outlook hangs, and the servers drives get pounded by the way Outlook client to PST database works....naturally heavy traffic on the network too. Keep 'em local, or better yet...get Exchange.
 
What I do when pst gets huge is to start a new pst file
I have a new one on a flash drive, I close outlook copy and rename
Then go to - file/open old data file so they can see old emails.
They can drag important folders into new pst
This is a very fast way of doing it; don’t have to wait forever importing for onsite work.
With a huge pst it’s not going to get better only worse over time you might as well bite the bullet.
 
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@ tsxclub - Your best taking your computer to a IT technician. This forum is not for end users, which you apparently are.

You could try majorgeeks, or toms hardware for answers to your question.
 
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