具体原因未知，可能是跟同步有关。
以下是某人的问题：
This seems to be a common and frustrating problem, and I haven't been able to find an answer anywhere. My computer periodically tells me that Microsoft Office 2003 is synchronizing folders. While it's doing that - and it takes awhile - not much else can happen. I use only one computer, and I have nothing to synchronize. Can anyone tell me how to turn off synchronization?
Thanks so much!
答案：
In Outlook 2003, click Tools, E-mail Accounts, View or Change Existing E-mail Accounts. Select your Exchange profile and then click Change. Uncheck the "Used Cached Exchange Mode" checkbox. Close Outlook and restart it. Now search your system for a .OST file. This file is the local copy of your Outlook mailbox and is no longer needed. The date and time of the file should match the time you closed Outlook after turning the Cached Mode off. You can delete it.
另一个解决方案（因为这个问题不是总出现，现在不确定是否某个方案一定可以工作。）：
You guys had pointed me in the right direction, but today I have definitively solved this screwy mess. If you right click on each of the email folders and select "properties" you will see a check box: Automatically generate Microsoft Exchange views". UNcheck this box on each email folder. You will still get a very brief "synchronizing" message, but ONLY while it is actively linking to your POP account. Try it...
