BlagojKocovski
Programmer
We’re producing a CTI application named Callisto that involves integration with MS Exchange in order to load the address book and calendar information about the company users. The integration is done with the help of a service application named Exchange Connector (EC). The EC is written using VB 6.0 and is using the CDO 1.21 libraries in order to read contact and calendar data. The CDO is installed from Exchange 5.5 (with SP4 or post SP4 fixes) or Exchange 2000 CD, i.e. we don’t use Outlook CDO versions due to the security constraints implemented in those versions. The thing is that in order to read calendar appointments for all the users in a selected address list, we must use impersonation, i.e. the Logon method, in the CDO Session object, with the “ProfileInfo” parameter. Since the EC service is run in the context of a user account which has the necessary permissions at the Exchange server, we logon to the different mailboxes in a loop and read the appointments in a given date range. However, since recently, on some of the customer sites the Logoff method started to throw an error with number -2147417848 and description “Method '~' of object '~' failed”. Actually, it is not only the Logoff method that throws this error, sometimes accessing a property of an appointment, e.g. Location throws the same error. The final presentation of the problem is that the EC service completely hangs. Monitoring the number of threads in the Task Manager for the EC service process, we’ve noted that the number of threads is decreased when this happens, i.e. the method or the property hangs.
Searching on the web, we found the following post in the Wrox discussion forum archives. The information provided by David matches pretty closely the happenings in our EC service too. I know the problem David saw was with ASP, but we think it is general and not related only to ASP … However, there is no information about a possible workaround in this post… We also tried to find a workaround or any CDO update that solves the problem, but with little help. We found a suggestion on MS support web ( but this suggestion assumes we know the passwords for all the users we need to impersonate, which is not the case in our situation, thus we can’t create different processes for each mailbox access…
Interestingly, the problem didn’t face up until recently, i.e. wasn’t showing in year 2003, so however strange it may sound, we’re fearing that we may face a bug that is somehow connected to the fact that 2004 is a leap year or connected to some date-based calculation or similar…
Thank you in advance …
Searching on the web, we found the following post in the Wrox discussion forum archives. The information provided by David matches pretty closely the happenings in our EC service too. I know the problem David saw was with ASP, but we think it is general and not related only to ASP … However, there is no information about a possible workaround in this post… We also tried to find a workaround or any CDO update that solves the problem, but with little help. We found a suggestion on MS support web ( but this suggestion assumes we know the passwords for all the users we need to impersonate, which is not the case in our situation, thus we can’t create different processes for each mailbox access…
Interestingly, the problem didn’t face up until recently, i.e. wasn’t showing in year 2003, so however strange it may sound, we’re fearing that we may face a bug that is somehow connected to the fact that 2004 is a leap year or connected to some date-based calculation or similar…
Thank you in advance …
