Hi,
There are several check point:
1. System time is exactly right time.
2. Outlook client version with latest rollup
3. If you are trying to configure online, make sure you are using:
1)Asia: https://disco(dev).crm5.dynamics.com
2)EMEA: https://disco(dev).crm4.dynamics.com
3)NA: https://disco(dev).crm.dynamics.com
4. Microsoft Online service sign in assistance RTM version, beta version will not work
5. If Win 8, make sure WIF 3.5 feature is turned on
6. Local admin privilege for os of current login user
7. Sitemap contains no duplicated items, for example Account, Account(1)