Did you refer to the links below:

http://blogs.technet.com/b/jeff_stokes/archive/2008/11/25/how-to-get-rid-of-9646-events.aspx

https://support.microsoft.com/kb/2742012

http://blogs.msdn.com/b/dvespa/archive/2014/01/06/9646-on-exchange-2013-view-information-store-status.aspx

• Edited by Raritan Wednesday, February 04, 2015 11:21 AM second pic

Hi,

For this issue, please increase session level to check result.

1. Click Start, click Run, type regedit in the Open box, and then click OK.
2. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem
3. If the Maximum Allowed Sessions Per User entry does not exist, do the following:
   1. On the Edit menu, point to New, and then click DWORD Value.
   2. Type Maximum Allowed Sessions Per User as the entry name, and then press ENTER.
4. Right-click the Maximum Allowed Sessions Per User entry, and then click Modify.
5. Click Decimal, type the value that you want to set in the Value data box, and then click OK.
6. Exit Registry Editor.
7. Click Start, click Run, type services.msc in the Open box, and then click OK.
8. Click the MSExchange Information Store service, and then click Restart Service.

Hope this is helpful.

Best regards,

If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com

Hi Belinda,

Can you help me how can I get the user mailbox id or guid from Legacy DN id. In the above pic you can see the legacy dn value

• Edited by Raritan 4 hours 58 minutes ago add more comments

Hi Raritan,

the most easy way would be like

1. install the RSAT Active directory tools (add-windowsfeature rsat-ad-powershell)

2. import activedirectory

3. $dnuser  get-aduser -filter "(LegacyExchangeDN='DN-value from your event')"

That will return the corresponding AD user from your LegacyDN

4. get-mailbox $dnuser

That will return the corresponding mailbox object

In your case I would prefer to filter in AD than using get-mailbox for the same job.

Regards,
Martin