Troubleshoot corrupt definitions in Endpoint Protection

Article:TECH92043  |  Created: 2009-01-27  |  Updated: 2014-11-21  |  Article URL
Article Type
Technical Solution


This article provides troubleshooting information when one or more of the following is true:

  • Definitions fail to update
  • Definition information in the Windows registry is different from the information in the usage.dat file
  • There are duplicate product definition entries in the usage.dat file
  • The usage.dat product entries are using different definitions


Note: To quickly check if this issue still exists or has been resolved on the computer, download and run SymHelp.

Corruption of virus definitions may have many causes. Two contexts should be considered when responding to potentially corrupted content definitions:

  • Is the corruption believed to be a one-time issue with a suspected one-time cause?
  • Is the corruption a recurring issue due to an unknown cause?

Known, one-time cause

If the known or suspected cause is not anticipated to re-occur, you can clear corrupted definitions by uninstalling and reinstalling SEP. Alternately, you can manually clear definitions as follows:

Unknown cause, recurring issue

If the cause is not known, clearing the definitions can be a useful troubleshooting step even if it does not lead to a root cause.

If the problem is a recurring issue on one or more computers, then identifying root cause becomes more important, especially if it proves necessary to repeat the procedure for clearing corrupted definitions.

Consider the following when attempting to identify the cause for recurring definition corruption:

  • Hard drive space on the affected computer is less than 900 MB.

If a cause cannot be found or addressed and the issue repeats itself, contact Technical Support.

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