How to export to .ost

Question

I just brought my clients up on SBS 2011 with Exchange.  Prior to that, they were running without a domain and using Outlook with .pst files.  After joining each machine to the domain, each user's Outlook now talks to Exchange via .ost. 
How do I export all the .pst files and folders to the new .ost files?

Answer 1

I would join to the previous answer. Additionaly it is important that you follow the reccomendations for maximum .ost file size to avoid troubles in Outlook operations.
http://support.microsoft.com/kb/940226
When you use Outlook 2007 with the Performance Update, or you use Outlook 2007 SP1 versions before the February 2009 cumulative update, the following .ost size guidelines generally apply:
Up to 2 gigabytes (GB): This size should provide a good user experience on most hardware.
Between 2 GB and 4 GB: This size is typically hardware dependent. Therefore, if you have a fast hard disk and much RAM, your experience will be better. However, slower hard drives, such as drives that are typically found on portable computers
or early generation solid state drives (SSDs), experience some application pauses when the drives respond.
More than 4 GB: This size is where short pauses begin to occur on most hardware.
Very large, such as 10 GB or larger: This size increases the frequency of the short pauses, especially while you are downloading new e-mail. You can use Send/Receive groups to manually sync your mail. This synchronization minimizes changes
in the local data file during heavy e-mail usage. For more information about how to manage Outlook synchronization, visit the following Microsoft Web sites:
http://office.microsoft.com/en-us/outlook/HP052421871033.aspx (http://office.microsoft.com/en-us/outlook/HP052421871033.aspx)
http://office.microsoft.com/en-us/outlook/HP030829231033.aspx (http://office.microsoft.com/en-us/outlook/HP030829231033.aspx)
When you use Outlook 2007 SP1 with the February 2009 cumulative update or higher, the following .ost size guidelines generally apply:
Up to 5 gigabytes (GB): This size should provide a good user experience on most hardware.
Between 5 GB and 10 GB: This size is typically hardware dependent. Therefore, if you have a fast hard disk and much RAM, your experience will be better. However, slower hard drives, such as drives that are typically found on portable computers
or early generation solid state drives (SSDs), experience some application pauses when the drives respond.
More than 10 GB: This size is where short pauses begin to occur on most hardware.
Very large, such as 25 GB or larger: This size increases the frequency of the short pauses, especially while you are downloading new e-mail. As described above, you can use Send/Receive groups to manually sync your mail.