Technical Advisory – Windows patch triggers errors with Kerio Outlook Connector

A recent Microsoft Windows update KB2585542 (released on Tuesday, January 10, 2012) produces numerous errors with Kerio Outlook Connector (Offline Edition) and may result in Outlook being unable to send mail.  This bug only affects Windows users running any version of Outlook with the Kerio Outlook Connecter.

A fix for this is expected to be released by Kerio on January 12, 2012, and we will update all servers to Kerio Connect 7.3.1 Patch 2 on Friday, January 13, 2012 between 10:30PM & 11:00PM MST.


SSL error (mails are not sent) with MS KB2585542 installed

While using Kerio Outlook Connector Offline (KOFF), emails are not sent and the following error message is displayed (error 800CCC12)


Recent Microsoft Windows update KB2585542 (released on Tuesday, January 10, 2012, link) changes the winhttp.dll system library which is used by Kerio Outlook Connector (Offline Edition). The update changes the data flow in a network communication over TLS (SSL) secured connection used in HTTPS communication of Kerio Outlook Connector with Kerio Connect server. This change is not compatible with Kerio Connect server.

How do I know I’m affected? What are the symptoms?

Users may experience various symptoms, depending on Microsoft Outlook version they use. These symptoms include:

  • Microsoft Outlook shows an error while sending an email (error 0x800CCC12 – Cannot connect to network):


  • Kerio Outlook Connector is in offline mode after start of Microsoft Outlook:


  • Kerio Outlook Connector reports that user authentication fails after opening Microsoft Outlook:


  • It is not possible to configure new Kerio Outlook Connector account in Microsoft Outlook (error 0x80042004 – Unknown error):


  • Microsoft Outlook fails to start with error “0x8004010f MAPI_E_NOT_FOUND”:


How do I check if the update is installed?

To verify that open Control Panel, select Programs and then select Programs and Features and choose “Installed updates” option and look for “KB2585542” in Microsoft Windows section.


How do I fix it?

There are two possible workarounds for customers who don’t or can’t update to Kerio Connect 7.3.1 patch 2:

  • Open the Kerio Outlook Connector account configuration and disable “Use data compression” option in the account settings. To do so, open Control Panel, select Users accounts and then select Mail option. Click on the E-mail Accounts button and edit the account settings and uncheck „Use data compression” option in Server Details tab. Then click on OK and start Microsoft Outlook:


  • Uninstall KB2585542 from client computer. To do so, locate the “KB2585542” update in Control Panel/Programs and Features/Installed updates windows and select „Uninstall” option. This requires computer restart.


What Kerio Outlook Connector versions are affected?

Affected are all Kerio Outlook Connector versions on Windows XP, Windows Vista and Windows 7 with installed KB2585542 update.

I don’t use SSL am I affected?

No. If you don’t use SSL (HTTPS) for synchronization of Kerio Outlook Connector with Kerio Connect server then you will not be affected by the windows update.

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