Mac OS: Error Type 41

This article explains the cause of Error Type 41 and tells how to eliminate it.

During startup the computer presents a dialog box with Error Type 41. The computer stops responding and the desktop never appears. The same thing happens even if extensions are disabled. In some cases, the name of a software item may be in the message, such as "Time Synchronizer."

This article has been archived and is no longer updated by Apple.

Error Type 41 is not new and is not unique to any version of System 7, Mac OS 8, or Mac OS 9.

Follow these steps to troubleshoot the issue:

    1. Start up from your system software installation CD. See technical document 50055, "Miscellaneous Manuals".
    2. Locate Finder in your hard disk's System Folder, and move it to the Trash.
    3. Perform a reinstallation just the base system.
    4. If the issue persists, start up from the CD again and move the Fonts folder out of the System Folder.
    5. Perform a clean installation of the system software if the issue persists. See technical document 30691, "Mac OS: When & Why to Perform a Clean Installation".

Locking the Finder (in the "Get Info" window) may prevent the error condition from recurring. However, be aware that a locked Finder can cause some system software installations to fail. If using Mac OS 8, upgrading to at least Mac OS 8.1 may help prevent one cause of this issue.

If the error occurred immediately after installing some software, there may have been a failure during installation or you may have some incompatible software. Any time you are reinstalling software to correct an error or behavior, you should run Disk First Aid beforehand and repair any damage found by Disk First Aid.

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