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Unable to Obtain a Lock when Using PHYLock


Image for Windows reports that PHYLock cannot obtain a lock on a system containing third-party software/drivers that provide disk-related functionality.


Some drivers can interfere with I/O to or from the PHYLock driver.  This can prevent PHYLock from being able to obtain a lock or from working properly after it has.


  • Determine if the system contains one or more drivers that may be interfering with PHYLock. To do this, proceed as follows:

    1. Navigate to the following registry key:


    2. Locate the value named UpperFilters. By default, and with only PHYLock installed, the data for this value will contain phylock and PartMgr. If you see anything else, please double-click the UpperFilters value, select its entire contents, copy it to the clipboard, and paste it into an email to for review. TeraByte support will attempt to determine what software may be in use and if/how it is affecting PHYLock.

      Note: Do not make any changes to the UpperFilters value! Doing so can potentially cause serious problems, including rendering your system unbootable.

  • Use Microsoft's Volume Shadow Copy service (VSS) instead of PHYLock. To do this, enable the Use VSS When Available option in Image for Windows (this doesn't require a reboot). You must be running Windows 2003 or later.

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