Thursday, June 21, 2007

How many Recurring Appointments Does it Take to Screw Up Outlook in E2K7?

Editor's note: Yipee! As of 2/28/2008 Microsoft found and fixed this in the "Update Rollup 1 for Exchange Server 2007 Service Pack 1" (see:

The answer: 1300 (not 1301, we mean 1300)

While debugging our insertion technology for migrations from legacy calendaring systems into Exchange 2007, Russ decided to insert 23,000 appointments into a single calendar (which is not as rare a real-world occurrence as you might think).

When we narrowed th einsertion to just recurring items we found a hard limit at 1300:

Interesting variation on this: even with this error we have no problem adding one-time meetings or appointments -- but the second we try to make them recurring the error pops up.

We were really surprised to be getting CDO errors server-side, especially since CDOEXM is obsoleted and CDOEX is denigrated in 2007, and our new insertion code is based on EWS and has had all CDO-specific code ripped out of it with the diligence of a vegan removing meat and dairy products from their diet.

The specific Outlook error message: "There is not enough memory available to perform the operation." led us to some server-side errors that looked like this:

Exception type: Microsoft.Mapi.MapiExceptionNotEnoughMemory
Exception message: MapiExceptionNotEnoughMemory:
Unable to save changes. (hr=0x8007000e, ec=-2147024882) Diagnostic context
The event logs are EXCDO errors
Event Type: Error
Event Source: EXCDO
Event Category: General
Event ID: 8199
User: N/A
Calendaring agent failed in message save notification with error 0x8007000e on judy@lab.sumatra.local: /Calendar/test5.EML

We didn't find anything on specific 2007 problems, but this does sound very similar to an existing 2003 problem: You cannot save or delete a recurring appointment from a Calendar that is maintained on an Exchange Server 2003 computer, aka KB 892524.

So we wanted to put this up to let folks know and see if anyone else had been experiencing this problem.


Unknown said...

I 've got the same problem, but as you, I just found useless info that belongs to E3k or E3k3

Anonymous said...

Hello Zyg,

we have the same problem with the “Calendaring error” in our Exchange 2007 environment as you described in your blog article…

My questions are:
Did you find a workaround and did you contact Microsoft PSS working around the problem?
The last days we worked with “Microsoft PSS” around the topic and we hope we can reach that a Hotfix for this issue/bug will be provided.
If you have some more informationen about yout current situation with this problem, please let me know.

Best regards,

zyg said...

We don't bother telling Microsoft anything any more. It takes forever to convince them and we never see anything happen so it's a huge waste of time.

When we do a migration we usually have some latitude over how much history to take -- so this solves the problem when we run into it.

Anonymous said...

Hello Zyp,

we worked around the problem for a while and I finished a new blog posting. I think there is a good chance to get a hotfix for that problem from the Microsoft Exchange Development Team. The Hotfix Request is still pending since last wednesday. I'll kepp you up to date.

May be you like to read my experiences in the Weblog article ( It's wirtten in my local language (german), but may be this link with google translations help you...

best regards,
Markus Mohmeyer

Anonymous said...

I see you are having the same problem as i with the EXCDO 8199 errors... Have you found a solution?

zyg said...

We really haven't been working on a solution ourselves -- our read is that this is deep in Microsoft's code and we've learned better than to even TRY getting them to fix their problems. Zimbra on the other hand has been GREAT at fixing issues we find in migrations. Check out Markus' links -- he's latched onto this problem with the dedication of a pit bull and I need to commend him for that.

Anonymous said...

Hello Zyg and Jaymz,

okay, finally I did a new blog posting in suitably to the topic...


Microsoft built a hotfix and will increase the limit (possible "recurring appointment masters") from 1300 to a higher value.

So watch out for upcoming "Update Rollups" :-)
Thanks for your conversation with the topic.

best regrads,
Markus (

Anonymous said...

Been seeing basically the same problem in a public folder calendar that we use for scheduling. Unfortunately neither RTM rollup 6 nor SP1 with rollup 1 fix the problem. Anyone have any post-"fix" input?