I had a PC (XP Sp3) that connects to SBS 2003 server (Exchange 2003). after uprade to Office 2010, the task list become very slow. when I try to move a task (drag & drop), it takes about 20~30 seconds to finish. I used outlook webmail to check. the task list works very quickerly. And my mailboxes total size is 1.4Gb only. I re-create the ost file already, it doesn't help. check email and contact under outlook 2010 is very quick as well. Only task list is the problem. Any idea?