Hi

I have a problem with mailboxes that have connected a lot (40) of shared mailboxes. I know that's not really a good situation, but they need it because of a third party tool.

All mailboxes are connected, but my problem now is of course, that the users are unable to open all of the connected mailboxes. "Cannot open the folder.  The set of folders cannot be opened.  Microsoft Exchange is not available."

At the beginning I had these 9646 errors in the event log of the Exchange Server (exceeded the maximum of 32 objects of type Session). I added the registry key "Maximum Allowed Sessions Per User" with a value of 64. The error disappeared, but the users are still unable to open all mailboxes. There are no other warnings or error messages in the server eventlog.

The users must be able to open all these connected mailboxes. How can I achieve that?

Any suggestion would be appreciated!

Regards
Peter

Hello

after change registry restart Microsoft Exchange Information Store  services?

Sorry, yes Information Store service has been restarted

Hi Peter,

Thank you for your question.

If you use outlook 2013, please install KB2889859 by the following link to check if the issue persist:

https://support.microsoft.com/en-us/kb/2889859

If not, please post the snapshot of error to us.

If there are any questions regarding this issue, please be free to let me know.

Best Regard,

Jim

Hello Jim

KB2889859 is already installed.

The snapshot of the error message id in German, an it means "Cannot expand the folder. Microsoft Exchange is not available. Either there are network problems or the Exchange server is down for maintenance."

Regards
Peter

Hi Peter,

We could refer to the following link to create a new Outlook profile to check if the issue persist. To do this, follow these steps:

1. Exit Outlook.
2. In Control Panel, click or double-click Mail. 
3. To locate the Mail item, open Control Panel, and then in the Search box at the top of window, type Mail. In Control Panel for Windows XP, type Mail in the Address box.
4. Click Show Profiles.
5. Click Add.
6. Type a name for the profile, and then click OK.
7. Follow the Add Account wizard to add your email account. When you're done, click Finish.
8. In Mail, make sure that the Always use this profile option is selected, and then select your new profile name from the list.


If there are any questions regarding this issue, please be free to let me know.

Best Regard,

Jim