Diagnostics

✅ What is Diagnostics?

Diagnostics refers to the process of identifying and analyzing problems in computer hardware, software, and networks to determine the cause of issues and fix them.

👉 In simple words:

Finding out what's wrong with a computer or network and how to fix it.

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🔑 Types of Diagnostics:

Type	Description	Example Tools/Methods
Hardware Diagnostics	Check physical components like CPU, RAM, HDD.	BIOS/UEFI Diagnostics, MemTest86, Dell ePSA
Software Diagnostics	Check OS, drivers, and applications.	Event Viewer, System Logs, Safe Mode
Network Diagnostics	Analyze connectivity and performance issues.	PING, TRACEROUTE, NETSTAT, ipconfig
Security Diagnostics	Check for viruses, malware, and vulnerabilities.	Antivirus, Windows Defender, Malwarebytes
Performance Diagnostics	Find reasons for slow system/app performance.	Task Manager, Resource Monitor, top (Linux)

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⚙️ Common Diagnostic Tools and Utilities:

1. Built-in System Tools:

Tool	OS	Purpose
Task Manager	Windows	Monitor running processes, CPU, RAM usage.
Event Viewer	Windows	View system/application error logs.
System Information (msinfo32)	Windows	Full system specs and hardware info.
Device Manager	Windows	Check and update device drivers.
Performance Monitor	Windows	Advanced performance analysis.
Activity Monitor	macOS	Monitor CPU, memory, and disk usage.
Console Logs	macOS	View system and application logs.
System Logs	Linux (e.g., /var/log/syslog)	System events and errors.

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2. Hardware Diagnostics Tools:

Tool	Purpose
MemTest86	Test RAM for errors.
BIOS/UEFI Diagnostics	Built-in hardware tests in BIOS (e.g., Dell, HP).
CrystalDiskInfo	Check hard drive health (SMART data).
CPU-Z / GPU-Z	Check CPU/GPU status and temperature.
HWMonitor	Monitor hardware sensors (temp, voltage).

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3. Network Diagnostics Tools:

Tool	Purpose
PING	Check if a device is reachable.
TRACEROUTE/TRACERT	Find the route and latency to a destination.
ipconfig/ifconfig	View and configure network interfaces.
NETSTAT	View network connections and listening ports.
nslookup	DNS resolution check.

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4. Security and Malware Diagnostics:

Tool	Purpose
Windows Defender	Built-in antivirus for Windows.
Malwarebytes	Detect and remove malware.
ESET Online Scanner	Online virus scan.
Kaspersky Rescue Disk	Bootable antivirus for deep scan.

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🔍 Common Diagnostic Commands (Windows):

Command	Purpose
sfc /scannow	Scan and repair corrupted system files.
chkdsk /f	Check and fix disk errors.
DISM /Online /Cleanup-Image /RestoreHealth	Repair Windows image.
ipconfig /all	Show detailed network configuration.
netstat -ano	List network connections with PID.

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🚦 Common Diagnostic Process (Step by Step):

Step	Description
1. Identify Problem	Collect symptoms and error messages.
2. Gather Information	Use diagnostic tools to check system status.
3. Isolate the Issue	Determine if it's hardware, software, or network.
4. Test Solutions	Apply fixes or workarounds step by step.
5. Monitor Results	See if issue is resolved; test system performance.
6. Document the Fix	Note solution for future reference.

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📊 Examples of Diagnostics in Action:

Problem	Diagnostic Tool/Method	Possible Cause
Slow Computer	Task Manager, Resource Monitor	Too many background apps, malware, low RAM.
Frequent Crashes	Event Viewer, sfc /scannow	Corrupt system files, faulty RAM/driver.
No Internet Connection	PING, ipconfig, router diagnostics	IP config issue, router problem.
Blue Screen (BSOD)	Event Viewer, Windows Memory Diagnostic	Faulty driver, hardware issues.
Unrecognized USB Device	Device Manager	Driver issue, hardware failure.

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✅ Benefits of Diagnostics:

Benefit	Why Important
Prevents Major Failures	Fix issues early before bigger problems arise.
Saves Time and Money	Avoid unnecessary repairs or replacements.
Improves System Performance	Identify and remove bottlenecks.
Enhances Security	Detect malware or vulnerabilities.
Accurate Troubleshooting	Pinpoint exact cause, avoiding trial-and-error.

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📌 Summary:

Aspect	Details
Definition	Process to identify and fix system issues.
Types	Hardware, software, network, security.
Common Tools	Task Manager, Event Viewer, sfc, PING, BIOS.
Steps	Identify, analyze, isolate, fix, monitor.
Goal	Restore system to normal, efficient operation.