Upgrading to Outlook 2007 and OST Files

[Dave Hahn]

hi,

My company is getting ready to deploy Office 2007 and uninstalling Office
2003.

I have a concern with the Outlook upgrade. In my testing, if I tell the
installer to modify existing exchange profiles to match our settings, Outlook
will re-download a copy of the users mailbox. If I change the installer to
NOT modify existing profiles if they exist, there is still some sort of
migration that goes on when the user launches Outlook for the first time.

I need to verify that in that case, Oulook will NOT download the user's
entire mailbox again. This is undesirable as it could cause performance
issues if a large number of users in an outer office get upgraded to Outlook
2007 at the same time.

Can someone clarify Outlook's behavior in this case with regard to the OST
file? Is it preserved when you upgrade from Outlook 2003? I am using the
Office Customization Tool to create a custom installation of Office.

Thanks,
David.

 

[Brian Tillman [MVP - Outlook]]

I have a concern with the Outlook upgrade. In my testing, if I tell the
installer to modify existing exchange profiles to match our settings,
Outlook
will re-download a copy of the users mailbox. If I change the installer to
NOT modify existing profiles if they exist, there is still some sort of
migration that goes on when the user launches Outlook for the first time.

I need to verify that in that case, Oulook will NOT download the user's
entire mailbox again. This is undesirable as it could cause performance
issues if a large number of users in an outer office get upgraded to Outlook
2007 at the same time.

If you reuse the existing mail profiles, I'm fairly sure the OSTs will be
reused in the new Outlook. I haven't tried it, though. I'm fairly sure,
however, that if you create a new profile and re-add the Exchange account that
Outlook will create a new OST.

 

[Dave Hahn]

Thanks for the reply, Brian.

In my testing the behavior you are describing seems to work. Although a few
times I got a message that my OST file was old and I should re-create it.
What causes this?

I am using VM's to do my testing and I thought it might have something to do
with the fact that the snap I was using was very old (about a month). I
opened Outlook 2003 once to let it update my OST before upgrading. I still
ended up getting the message a few times, but not consistently.

Any ideas?

Thanks,
David.

 

[Brian Tillman [MVP - Outlook]]

In my testing the behavior you are describing seems to work. Although a few
times I got a message that my OST file was old and I should re-create it.
What causes this?

If Outlook detects particular sync discrepancies between the OST and the
server you might see this.

 

[neo [mvp outlook]]

There are two OST types when running against Exchange. You could be running
in Unicode (preferred for Exchange 2000/2003/7) or ANSI (Exchange 5.5).
Outlook 2003 doesn't force a recreation of an OST when moving from Exchange
5.5 to a later version (e.g. Exchange 2003). Not sure If Outlook 2007 will
do this or not.

If you want to check what mode Outlook is running in against Exchange,
r-click on Mailbox - Username folder and select Properties > Advanced button

Advanced tab. There are options where you can instruct Outlook to toss

the .OST if it is an ANSI format and create a new one in Unicode format.