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For each of the detection engines the following items are shown:
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Available
Indicates whether the specific detection engine is available (working). The way to test the availability is specific for each of the detection engines (for local antiviruses it is a test file scan, for sandboxes it is test API call, internal modules are always available). If the engine is not available and is not enabled already, it cannot be enabled, until it becomes available. If some unavailable engine is enabled, the application does try to perform the checks (although they will probably fail).
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