Hi Soofi,
Answers for you:
-> What exactly is the error message means ?
Ans: This means that WAE clock is not synced correctly and is out of sync with NTP. This could cause issues while generating reports / statistics. Please note that thsi issue will not affect optimization.
-> How do I fix this ?
Ans: Please make sure that following points are met.
1. NTP is configured on WAE, pointing to actual NTP server (not the central manager).
2. Please make sure WAE can reach NTP, UDP port 123.
3. Please make sure to use a valid NTP server.
4. Timezone sync ups are also useful if you want more accuracy.
More details here: http://www.cisco.com/en/US/docs/app_ntwk_services/waas/waas/v421/configuration/guide/other.html#wp1042418
Hope this helps,
Regards,
Bhavin.