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All messages having a level ERROR or FATAL should be acknowledged to identify that the message has been seen and appropriate action taken.
A A message having a level WARN can be acknowledged as well but is only needed to remove the opaque warning icon in the status bar if in the explorer.xml <showIconForUnacknowledgedWarnings>true</showIconForUnacknowledgedWarnings> is configured which is false by default. See 01 FEWS Explorer#01FEWSExplorer-showIconForUnacknowledgedWarnings.
Double click the icon to acknowledge a message or click the Acknowledge button. Multiple messages may also be selected and acknowledged in a single action.
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