Symptoms

Throughout the day the k2 workflow will stop loading, gives "Page cannot be displayed". A server restart resolves the issue for a period of time.
 

Diagnoses

Checking Kerberos logs shows the errors "KRB_AP_ERR_TKT_NYV" and "KRB_AP_ERR_SKEW". "KRB_AP_ERR_TKT_NYV" means Ticket Not Yet Valid, which usually happens with the time of the client and the server are out of sync.

Checking the server time and comparing it to the local machine shows a discrepancy in times.

Changing the server time manually to be in sync with the client fixes the issue temporarily

Try running the command "w32m /query /status" on the K2 server, which will show the time source as well as the last successful sync.
 

Resolution

In this case, we checked the Windows Time service and found that it was not running. We started the Windows Time service on the server and ran the command again, and found that it was synching from the CMOS time instead of the domain controller. After waiting a few seconds, the server synced time from the domain controller correctly, and Workspace became accessible.