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Very Weird Outlook PST Problem


Distinguished Member

I have a sub folder in a PST file, that Outlook reports as being just over 800MB in size, yet it displays no items.

I have a copy of Kernal PST Repair tool at work so I opened the PST file using this, and sure enough it shows over 5300 emails, which is correct.

However, when saving to a new PST file using Kernal, the PST file size is tiny in comparison as it hasn't actually extracted any of the emails.

So why is Outlook not showing anything in the subfolder from the original PST file, yet reporting the subfolder as being 800MB+ in size. If I copy just this folder to another PST file natively in Outlook, the new PST file grows to over 800MB, but again shows no data.

There are no filters applied. I'm 50 zillion % positive with this as I have literally decompiled Outlook to make sure.

Plus other PST files work 100% A-OK.


Distinguished Member
Looks like opying the problematic folder to an Exchange mailbox has 'sorted' it.

I will try copying them back to a new PST and see what happens << Nope, no difference. Copying individual emails from the Exchange mailbox to a new PST seems to work though.

The actual folder must be knackered.
Last edited:


Active Member
You don't say which version of Outlook you are running, but I expect you have a filtered view of some form.

Right click the column headers in the "bad" folder.
Select "Customize..." from menu
I expect the "Filter" is not set to off - so turn it off.

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