Cannot edit Enterprise Calendar in Project Server 2010

I am configuring a new instance of Project Server 2010, have full administrator rights, and have run into a problem with the Standard Enterprise Calendar. If I try to edit it from PWA, after about 30", I get the "Unknown Error" Message, whether I actually open the "Change Working time" screen in Project Pro or not. If I do get there, whether I start in PWA or in Project Pro, I cannot enter any exceptions to the calendar.

I have looked at solutions to similar issues here in the forum and they do not solve my problems. Any suggestions would be appreciated.

Thanks.

Jeff