We're having an issue with some aspects of our calendaring. It's a single-server Exchange 2007 SP1 Update Rollup 6 installation that exhibits no other problems. We have about 35 users and I see errors akin to the following in my Application log all throughout the day. They appear almost every minute (but not on any schedule).EventType:ErrorEventSource:EXCDOEventCategory:GeneralEventID:8206Date:2/23/2009Time:9:27:45AMUser:N/AComputer:EXCHSRVRDescription:Calendaringagentfailedwitherrorcode0x8000ffffwhilesavingappointment.Formoreinformation,seeHelpandSupportCenterathttp://go.microsoft.com/fwlink/events.asp.Data:0000:4872536176696e67HrSaving0008:417070743a3a4872Appt::Hr0010:436865636b506174CheckPat0018:7465726e20666169ternfai0020:6c65642e204d6169led.Mai0028:6c626f783a6b6c69lbox:jdo0030:6e64626572674073e12345@m 0038:6177647573742e77 ydomain. 0040:73 com Users have complained of issues when trying to create, delete, and modify appointments on calendars. What should I be looking for? Thanks in advance for any help. pk

Hi, Please run Best Practices Analyzer in Toolbox first to do a health check. Then temporarily disable the third party software and restart Microsoft Exchange Information Store service. Then test the issue again. Regards, Elvis

Restarting the Information Store service does indeed fix the issue temporarily, but if history is any judge this issue will resurface in a few weeks. Should I be restarting the Information Store service on a regular basis? I've never read anything about that.pk