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- Go to System Preferences (can be found on the dock or by going to Apple menu > System
Preferences), and click Security. - In the Security section, click on the Firewall tab.
- If necessary, click the lock icon on the lower left, and enter your OS admin password to
allow changes to be made. - If not already set by default, Select Set access for specific services and applications
so that the listed services are allowed through the firewall.
6. Extend your warranty
See computer purchase and warranty recommendations for information on purchasing the appropriate warranty coverage.
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