Hi

A client of mine is experiencing a strange phenomenon in Outlook 2013 32bit (Windows 7 64bits)

Yesterday he was sorting his emails and moved a few into sub (/sub/sub/...) folders

This morning he tried to access one of these emails, in it's present sub folder, and just as Outlook had finished displaying the contents of this folder, the sought email disappeared before his very eyes ! This isn't the first time he experiences such a behaviour by Outlook

I connected up to his account from my PC using Thunderbird and when I view the contents of the folder mentioned above I see its contents, missing email included

We checked other folders and realized that Outlook, compared with Thunderbird, isn't displaying the entire contents of these folders

I tried to check whether there were any filters enabled in the View menu but couldn't find any (maybe this is configured elsewhere ?)

I copied the missing email to his Inbox and asked him to transfer it back to the desired sub folder again : and now he sees it in its new destination (I however see two copies of it under Thunderbird)

Incidentally the Synchronization error folder contains over fifty thousand errors; should we heed the high quantity of these errors or ignore them ?

Any ideas on what could be causing this Outlook issue ?

Two weeks ago I split his OST file, by archiving part of it to a PST, because the file had reached 28 GB
The created archive is 10 GB in size, while the OST file has now shrunk to 5 GB. I can't explain what happened to the missing difference (13 GB)

thanks
yann

PS
Why does the Office setup install Office in 32bit mode by default (on 64bit systems) ?