Comprehensive and Detailed In-Depth Explanation:
If users can access local network resources but not the internet, the most likely culprit is a misconfigured or missing default gateway. The default gateway routes traffic from the local network to external networks (i.
e., the internet). If it's not properly set or was altered during a firewall update, internet traffic won't be forwarded correctly.
* Option A: Static IPs could cause conflict, but wouldn't affect only external access if configured correctly.
* Option C: An incorrect subnet mask could isolate devices, but local communication would likely be impacted too.
* Option D: VLANs segment networks; while misconfigured VLANs could cause access issues, they'd more likely isolate local traffic as well.
CompTIA A+ Core 1 Exam Objective Reference:
* Objective 2.6: Given a scenario, configure and troubleshoot network connectivity.