Dell OptiPlex GX60 System User's Manual page 153

computer start-up:
ALERT! Cover was previously removed.
12. Reset the chassis intrusion detector
NOTE: If a setup password has been assigned by someone else, contact your network administrator for information on resetting the chassis intrusion
detector.
13. Verify that your computer works correctly by running the
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by changing Chassis Intrusion to Enabled or Enabled-Silent.
Dell Diagnostics.