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Troubleshooting tips


Q - I did everything according to the admin guide. Followed the correct order for permissions in exchange, checked the com+ identity etc. etc. still when I use step 2 the application crashes and gives Access Denied and step 3 gives messages about certificates and all...

A - log on as Administrator and open Exchange System manager.

Browse to the Mailbox Store and do Properties - Security to locate the Exchange Domain Servers group in the list.

Check if in the list of permissions you see a Black tick in the DENY column for Send As or Receive As. If so remove that tick.
(A grey tick may still be visible but that is not a problem, it will be overruled by the explicit Allow that you set for gcadmin.)

Q - I did everything according to the admin guide and everything looks good, I can create group calendars, connect users to them and get a green box when I share their calendars in step #3.. still nothing appears in the groupcalendars.

A - Try this : Start - Run: regsvr32 "C:\Program Files\Exchsrvr\bin\exodbprx.dll"
Note C:\Program Files\Exchsrvr is the folder where Exchange Server is installed.

B - (ex2k3) Open the Mailbox store where the users have the mailboxes and open the Mailboxes object to list all mailboxes
Sort by name and browse down to locate the SystemMailbox object. It should be there and it should not have a red cross!
The SystemMailbox object is vital as this article explains http://support.microsoft.com/kb/316622

The quickest way to fix a missing SystemMailbox object is to create a new mailbox store. After that move the user mailboxes from the old to the new store.
We can remotely assist you with this task. Use the chat option to request help.

Q - I see duplicates in the groupcalendar for recurring items.

A - Update to version 1.4.16 and find a new setting in config.ini


Increase the value from 0 to 15 in steps of 2 until the problem is over when new recurring items are being created.
To remove existing duplicates it is sufficient to open the series in the personal calendar and close/save it.

Q - It's not working at all ....

2 answers:

#1: Call or email us. it's the fastest method for you to resolve the problem. For us.. we like to hear about problems so we can prevent them in future versions.

#2: Try the following

Did you reboot the server? If not, do that first.

Please start the troubleshooting quest with one user only. Do all steps hereunder.. no shortcuts please.

  • Open AD users & computers for that user.
  • Check the Primary Email address and copy the part before the @  so jack@opusflow.com would give 'jack'
  • Put that name in the Exchange Alias field (exchange general)
  • In the General tab, delete everything in the Description field that you did not put in there.
log on to the exchange server with gcadmin account
  • open gcadmin.exe from c:\exchange groupcalendar
  • check step #1, click both buttons on the left (no error?)
  • create a new calendar on the right (name it TEST)
  • check the general settings (if only out of office is ON you will see nothing but OOF items in all calendars)
go to step #2 and select the test user (jack)
  • map him to your newly created TEST calendar only
 go to step #3
  • select the test user (jack) again and disable sharing (red) and share it again (green)
open the com+ service manager until you see the ExchGC component on the right pane.
see the "ball in the box" with the plus sign on it ?  Is it running?  If it is, right click and shut it down.
Keep an eye on the ball and now create an item in the test-user's personal calendar
 Look at the ball again... It should be turning in the box and stop after one minute if no other users create items.

If it's still not working, enable logging in the gcadmin tool. Close and open the gcadmin tool, create an item in a personal calendar and send the gcadmin errorlog + eventlog + errorlog to info@opusflow.nl 

Q - It works for some but not for all users.

A1 - Make sure that the users where it does not work realy use the calendar that is part of their Exchange Inbox folders. Some users enter calendar information in a PST file calendar and Exchange server can't get to that.
A2 - Make sure that the users who participate in one of the Group Calendars are not member of a protected "Admin" group. Ref. article:

A3 - When sharing users in step 3 works ok but some of your users don't get their items replicated to the groupcalendars.... AND you have multiple mailbox stores, check if all mailbox stores have a system mailbox. If the problem is a missing system mailbox (ref:http://support.microsoft.com/kb/316622 ) you may see that all users in one mailbox are working correctly while the users in the other stores don't trigger the com+ component at all. No error log or event log will be created either.

Q - It worked for "a year" and suddenly it stopped working!

A1 - 

  • Enable logging (tick the box at the start page of the gcadmin tool) and delete the errorlog.txt file and eventlog.txt file from c:\exchange group calendar.
  • Create some new appointments in a user calendar.
  • If a new eventlog or errorlog is created, it's probably a configuration problem. Check the configuration or send the log files to opusflow for advice.

A2 - 

  • If you see no eventlog or errorlog with a recent file date in c:\exchange group calendar, the processing component is not operational at all.
  • Check the server eventlog for errors. If you see this error: Microsoft Exchange OLEDB was unable to either create an event sink object or get necessary interface(s) from the sink class specified by ExchGC.Application. do the following
    • In control panel / add&remove programs / uninstall Exchgc (this removes the com+ component)
    • Reboot the server
    • Run the MSI file from the downloaded EGC install zip file. (this installs the com+ component)
    • Adjust the identity of the ExchGC component in Component Services (identity of gcadmin)
    • Start and close the gcadmin.exe tool to have it re-register the exchgc.dll 

A3 - If you changed the password for the gcadmin account, make sure to adjust it as well for the com+ component in component services.

A4 - If you installed a new file level server virus scanner or adjusted the settings, make sure that it does not scan any exchange server directories. 

A5 - make sure that the 'Send As' permissions are in place for the gcadmin account. (admin guide, step B)

A6 - If you changed the default email policy of the exchange server.. delete the old exchange name from the config.ini file

A7 - Call or email us. Include your log files as an attachment please.

Q - Can't see all recurring items in outlook 2003 cached mode favorites folder. (outlook bug)

We use Outlook 2003 SP2 with Microsoft Exchange 2000 SP3 and in order to add the group calendars to my Other Calendars section on the Outlook Calendar view I must first browse the Folders tree, right-click the chosen Calendar and select the Add to Favorites option.

At this point I notice something odd - when I view the calendar within the Favorites folder only the first appointment of any recurring task is shown. However all of the appointments are still visible in the original calendar contained under the Public Folders. Consequently when I then add the calendar from the Favorites section to my Other Calendars section I also do not see any recurring appointments after the initial appointment.

A - After disabling the 'Download Public Folder Favorites' in Cached Exchange Mode Settings section on the Advanced tab of the email account properties this now works fine - you can still leave 'Use Cached Exchange Mode' enabled though.
Note that the old style offline store functionality is still available in Outlook. So for users that want to take the groupcalendar offline, configuring an OST file (in exchange properties of the profile) is a good workaround.

here's a tutorial http://www.msexchange.org/tutorials/Configuring_Outlook_2003_for_Offline_Use.html
It is possible to (fig. 6) tick cached mode, tick Download public folder favorites, click the offline folder settings button and then untick cached mode.


Q - Can't use blanks for calendar names.

A1 - Workaround 1 ; Use underscores for blanks ie _ 

A2 - log on to Outlook with the gcadmin account and create the public calendar folder with the name you need under the groupcalendar root folder.

Q - Runtime error: '-2147016656 (80072030)': Automation Error. There is no such subject on the server

A - The GCADMIN account is not a member of the exchange domain servers group. (admin guide step B)

Q - error: -2146105340 Unknown Error or  -2146105340 Method '~' of object '~' failed

A - Known to be raised when the default email policy of the Exchange server was changed. Fix this by removing the exchange name
from the config.ini file. The correct name will come back automatically.

Q - error: -2147467259 in the "gcadmin errorlog.txt" when trying to "share" a user-calendar in step #3

A - Delete the Exchgc com+ component from Component services - computers - my computer and run the MSI installer from the zip file.
after that, open the com+ component and adjust the identity to the gcadmin user.

Q - The default location of the groupcalendar root folder can't be used in our organization. We have access to one subfolder only. (we can not access the 'All public folders' root but only our company subfolder called 'CompanyX')

A1 - To work around this problem do the following:

1- log on to a workstation with the gcadmin account and connect outlook to the exchange server.
2- Open the public folders root folder for your company
3- Create a new folder of type Calendar (appointment items) and name it GroupCalendars or any other name you want.
4- log on to the exchange server and use the explorer to find CONFIG.INI in c:\Exchange Group Calendar
5- Open CONFIG.INI and locate the entry:   GroupCalendars top level folder=GroupCalendars
    changed that into: GroupCalendars top level folder=CompanyX/GroupCalendars

CompanyX is the public folder where you have access to
GroupCalendars is the name of the folder you created in Outlook (step 3 of 5)


Q - GCAdmin.exe starts with an error.

A1 - You might be running it on a test server. Run it on the real Exchange server or set up a test server with a separate organization and dns.
A2 - Enable error logging by ticking the checkbox. Restart the tool and send the logs over to

Q - error numbers in the error logs

A1 - error  -2147217895 or -2147024891
The account running the COM+ ExchGC component does not have an associated mailbox with Owner permissions on the Group Calendars.

A2 - error -2141913011
Right-click the 'ExchGC' component in Component Services, go to Properties and set it to a server application on the Application tab. Make sure the account password
is correct.

Q - Nothing appears in the group calendars (after creating a new item in my calendar I don't see it on the GroupCalendars)

A1 - Remove the account you are using to start the COM+ component from the Exchange server objects and add it again using these steps:

  • Open the Exchange System Manager.
  • Navigate through the server tree until you reach your server. For example, you might need to click through an administrative group and a server group.
  • Right click on your server. A pop-up menu appears.
  • Click Properties
  • Click the Security tab.
  • Find the gcadmin account in the list that appears and remove it if it is there. (you will re-add it later) Make sure the account is no longer listed.
    • Browse further down to the Mailbox store and Public folder store
    • Right click the 'Mailbox store'. (the place where the groupcalendar users have their inbox)
    • Click Properties
    • Click the Security tab.
    • In the Name dialog box, click Add and then select the new account (f.i. GCADMIN)  from the list that appears.
    • Select Full Control for the permission level.
    • Set the same permissions on the 'Public Folder Store' and after that (up the tree) also on the Server node.
    • Click Okay and wait at least 20 minutes for the permissions to be applied internally. 


A2 - Check the Exchange Alias of the user who's appointments are not being displayed. Change the alias into the partial email address that comes before the '@' sign. (if email address = JJackson@domain.com, make the exchange alias: JJackson) and try again.

A3 - If the com+ component (exchGC) ball starts turning in response to the creation of an item in a personal calendar but nothing appears in the group calendars: Enable error logging on the first page of the gcadmin tool. 
If you see no event log in the c:\exchange group calendar directory when you create an item in one of the personal calendars, wait for the com+ component ball to stop turning and run the setup again from the zip file you downloaded. (run the .exe not the .msi)

Q - Items appear in the group calendars but they don't disappear or duplicates appear.

A1 - Grant the account you are using to start the COM+ component full access to the Public Folder Group Calendars.

Q - Appointments with a slash in the subject are being ignored. They don't show on the group calendar.

A - A confirmed bug. This was fixed in version 1.312 

Q - On initial testing we had setup some group calendars with test names. Now we're trying to setup calendars with real names (some the same as the test names). The problem we're having is that users are still linked to the old calendars, even though I've used the admin tool to stop their sharing and disconnected the mappings.

A1 - You deleted the calendar folders before you un-mapped them from the users in step #2. It is very simple to fix this.

- in the gcadmin.exe tool select the user in step#2. The tool will offer you to remove the incorrect calendar mapping from this user.


- Open the active directory and a user in it.
- in the description field, remove the part : groupcalendars> bla bla + bli + blo < groupcalendar
this cleans it properly and you can remap the users to your new groupcalendars.

Q - Hidden items still show up when the body of an appointment contains @@@

A1 - Open gcadmin.exe step #1 - General settings. Remove the checkmark of the first option, close the form and reopen to check the option again. (this bug was fixed in the current version)

Q - Error in step #1 when creating the root folder or Group Calendars.

A1 - Make sure that the gcadmin account you are logged on with has all user rights.
(Use notepad to  open, change and save config.ini logged on as gcadmin)
A2 - When running it on a test server; The Exchange Domain Servers group must have the correct permissions to the mailbox’s within the Exchange mailbox store on that test server!

Q - Error in step #2 when connecting a user to a Group Calendar.

A1 - Make sure that the gcadmin account you are logged on with has all user rights and is not restricted by local/domain policies which prevents it from writing and reading values from the Active Directory. A simple test is to open Users & Computers, Open a user object and change the value of the DESCRIPTION field. If this fails the GCADMIN account is restricted.
A2 - Your domain controller may be down.

Q - Error message when trying to enable calendar sharing for a user (step#3) (7 possible answers)

A1 - Confirm that you installed the Com+ component (ExchGC) in component manager and make sure the identity and password are set to use the GCADMIN account. (note: NEVER right click and START the component manually. This will prevent it from working correctly)

A2 - Check the user account of the user that you try to enable sharing for. The 'Exchange Alias' or 'short name' must be the same as the email address part that comes before the @ sign.

A3 - Make sure you are logged on with the gcadmin account to the Exchange console.

A4 - Confirm that the users mailbox is on the same Exchange server as the one you logged on to.

A5 - On Exchange 2003 there might be something else causing problems. To check this, try to restart the "COM+ Event System" service in the services control panel. If the service refuses to stop and times out with an error try the following:

- In control panel - Add/Remove programs, uninstall the ExchGC component.

- Reboot the server.

- Try to restart the "COM+ Event System" service in the services control panel. This should work fine now.

- Install the .MSI file from the setup Zip file you downloaded from this website.

- Configure the Com+ component (ExchGC) in the Component Manager with the GCADMIN account and password.

A6 - Check the Com+ component. If the 'ball with plus sign' is spinning in its box, right click the component and shut it down. Try again to share a user calendar.

A7 - If the solutions above all fail, there might be a restriction (deny) on the the "Administrators" or "Exchange Domain Servers" group to access users mailboxes and calendars. In that case remove the gcadmin account from those groups and make sure that the gcadmin account has been granted access to all mailboxes and Public Folders as described in step C of the administrator guide.

Q - Errors  when you try to install the MSI file of the Com+ application

A - for error number 2755.1601

1. Click START, and then click RUN.
2. In the OPEN box, Type msiexec /unreg, and then click OK
3. When this process is complete, click START, and then click RUN.
4. In the OPEN box, type msiexec /regserver, and then click OK.


1. Open Control Panel - Add/Remove programs
2. Look for ExchGC and uninstall it first if it's there.


1. Open Administrative tools / Services
2. Make sure the services called:

"COM+ System Application" and  "Distributed Transaction Coordinator"
are not disabled.


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