Download the official, server-matched installer for the Kerio Outlook Connector .
The file is a critical dynamic link library component belonging to the Kerio Outlook Connector (Offline Edition) , commonly abbreviated as KOFF . This file serves as a proprietary Messaging Application Programming Interface (MAPI) service provider, enabling Microsoft Outlook to synchronize data natively with a Kerio Connect mail server. When this file is corrupted, unmapped, or blocked, users are completely locked out of their email client with severe runtime crashes. Anatomy of the KOFMSP.DLL Error
If you encounter this blocking error, use the following technical walkthroughs to restore functionality.
Open the and navigate to Programs and Features . Locate Kerio Outlook Connector (Offline Edition) . Select Uninstall . Restart your computer. kofmsp.dll
: If the file is there but not working, open Command Prompt as Administrator and run: regsvr32 kofmsp.dll
To check your version: Right-click kofmsp.dll → Properties → Details → File version.
"The information service C:\Program Files (x86)\Kerio\Outlook Connector (Offline Edition)\KOFMSP.DLL cannot be loaded." Why Do KOFMSP.DLL Errors Occur? When this file is corrupted, unmapped, or blocked,
If the problem persists, it may be due to corruption within Windows system files. Run these command-line tools as Administrator:
The kofmsp.dll error is almost exclusively a problem within the software. By following the steps to remove, reinstall, or repair the connector, you can quickly restore email functionality.
Click on your username or the option at the bottom to download the latest KOFF installer. Locate Kerio Outlook Connector (Offline Edition)
If you still intend to use Kerio, download the latest version of the Kerio Outlook Connector to ensure the kofmsp.dll file is correctly registered in the system.
Click on all windows, reboot your PC, and launch Outlook. Technical Compatibility Matrix Requirement 32-Bit Systems 64-Bit Systems Supported OS Windows 7, 8, 10, 11 Windows 7, 8, 10, 11 (Windows XP Not Supported) Outlook Bit-Version Requires 32-Bit KOFF Requires 64-Bit KOFF (Added in KOFF v7.0+) Target Storage Path
If you are locked out of your Outlook client because of a kofmsp.dll failure, the root cause usually falls into one of these four technical categories: Trigger Cause Technical Behavior
: The kofmsp.dll error might be caused by a corrupt Outlook profile. To rule this out, go to Control Panel > User Accounts > Mail . In the Mail Setup dialog, click Show Profiles . Select the profile associated with Kerio (it may be named "Kerio") and click Remove . Once deleted, create a new Outlook profile.
A: No. It is highly recommended not to download individual .dll files from third-party sites. These are often outdated or infected with malware. The only safe way to obtain this file is to reinstall the official Kerio Outlook Connector .