v1.0.6

ntchk v1.0.6 - Subnet & CIDR Calculator

Release Date: March 7, 2026

📥 Download & Install

📦 Release Assets (2 files required)

File	Description
ntchk-v1.0.6-Portable.zip	Main application package
ntchk-v1.0.6-Portable.zip.sha256	SHA256 checksum for verification

⬇️ Download both files from the Assets section below

🔒 Security First

⚠️ Always verify the checksum before running! See the File Verification section below.

🚀 Quick Installation

1. Download both files from GitHub releases
2. Verify the download using the .sha256 file
3. Extract ZIP to any folder (USB drive, network share, local drive - all supported)
4. Run ntchk.exe (recommended) or ntchk.bat
5. Done! No installation, no registry changes, fully portable

---

🎯 What's New

🔢 Subnet & CIDR Calculator — New Tab

A full subnet and CIDR calculation tool has been added as a new "Subnet Calc" tab, located between Diagnostics and Settings.

Subnet Calculator

Live classful subnet math. Select Network Class (A / B / C), enter an IP address, pick a subnet mask — all fields update instantly:

Field	Description
First Octet Range	Valid first-octet range for the selected class
Hex IP Address	Dotted hexadecimal representation of the IP
Wildcard Mask	Inverse mask for ACL use
Subnet Bits	Number of bits borrowed from the host portion
Mask Bits	Total prefix length
Maximum Subnets	Number of subnets available for the class
Hosts per Subnet	Usable host addresses per subnet
Host Address Range	First to last usable host address
Subnet ID	Network address
Broadcast Address	Directed broadcast address
Subnet Bitmap	Bit-level visual breakdown (class-id · network · host bits)

CIDR Calculator

Live classless CIDR math. Enter an IP address and select a mask length (1–32) — all fields update instantly:

Field	Description
CIDR Netmask	Subnet mask in dotted-quad notation
Wildcard Mask	Inverse mask for ACL use
Maximum Subnets	Total number of addresses in the block (2^host-bits)
Maximum Addresses	Usable host addresses (Maximum Subnets − 2)
CIDR Network	Network address of the block
Net: CIDR Notation	Network address with prefix (e.g. 192.168.1.0/24)
CIDR Address Range	First to last usable host address

All fields recalculate on every keystroke or dropdown change — no button required.

---

🛠️ Technical Notes

• New src/SubnetCalc.ps1 module — self-contained, no external dependencies, pure PowerShell arithmetic
• Integer arithmetic uses [Math]::Floor throughout to prevent PowerShell banker's rounding from corrupting octet values (e.g. 255.996… rounding up to 256)
• Class selection tracked via $Script:SubnetClass to prevent WPF nullable bool timing issues in deeply nested event handlers
• Light and Dark mode fully supported — uses existing dynamic resource brushes

---

🔄 Compatibility

• All existing features unchanged (Speed Test, Network Info, Diagnostics, Settings)
• Settings and configuration backward compatible
• No new dependencies

---

🔒 File Verification

After downloading, verify the ZIP integrity before running:

# Run in PowerShell in the folder where you downloaded the files
$hash = Get-FileHash "ntchk-v1.0.6-Portable.zip" -Algorithm SHA256
$expected = Get-Content "ntchk-v1.0.6-Portable.zip.sha256"
if ($hash.Hash -eq $expected.Trim()) { "✅ MATCH - Safe to extract" } else { "❌ MISMATCH - Do not run!" }

v1.0.5

ntchk v1.0.5 - Auto-Update Fix (Portable Mode)

📥 Download & Install

📦 Release Assets (2 files required)

File	Description	Size
ntchk-v1.0.5-Portable.zip	Main application package	1.29 MB
ntchk-v1.0.5-Portable.zip.sha256	SHA256 checksum for verification	64 bytes

⬇️ Download both files from the Assets section below

🔒 Security First

⚠️ Always verify the checksum before running! See the File Verification section below for step-by-step instructions.

🚀 Quick Installation

1. Download both files above from GitHub releases
2. Verify the download using the .sha256 file (see verification section)
3. Extract ZIP to any folder (USB drive, network share, local drive - all supported)
4. Run ntchk.exe (recommended) or ntchk.bat
5. Done! No installation, no registry changes, fully portable

---

🔧 Critical Update - Fixed Auto-Update Mechanism

This release fixes the infinite update loop issue that prevented v1.0.3 users from upgrading to newer versions.

✅ What's Fixed

Portable Update System

• Updates now download to extracted/ folder in the app directory (no more %TEMP% usage)
• Two-stage update process:
  1. Download update files to extracted/ folder
  2. Close application to release file locks
  3. Updater script copies files from extracted/ to app root
  4. Restore user settings and restart app
  5. Clean up temporary files automatically

Resolved Issues

• ✅ Fixed infinite update loop caused by file locking
• ✅ Fixed failed updates when .ps1 files were locked by running process
• ✅ Updater now runs in hidden window (no visible PowerShell console)
• ✅ All update files preserved in app folder (fully portable)

Automatic File Preservation

• config.json - Your settings are always preserved
• exports/* - Export history never overwritten
• Automatic backup and restore during updates

🛡️ Fully Portable & Safe

• No hardcoded paths - Works from any folder location
• No TEMP dependencies - Everything stays in app folder
• Network drive safe - Works on UNC paths and USB drives
• All paths dynamic - Uses $AppRoot parameter throughout

📋 Detailed Logs

Update process creates two log files for troubleshooting:

• upgrade-debug.log - Download and extraction details
• update.log - File copy operations and restart status

🧹 Code Improvements

• Removed debug message boxes from update workflow
• Cleaner error messages with log file locations
• Improved user experience during updates
• Hidden PowerShell window during update process

---

📥 Installation

For New Users:

1. Download ntchk-v1.0.5-Portable.zip
2. Extract to any folder
3. Run ntchk.exe (recommended) or ntchk.bat

For v1.0.4 Users:

• ✅ Auto-update works! Just click the upgrade button when prompted

For v1.0.3 Users:

• ⚠️ Manual update recommended:
  1. Download v1.0.5 ZIP
  2. Extract to a new folder
  3. Copy your config.json and exports/ folder to the new installation
  4. Future auto-updates will work from v1.0.5 onwards

---

🔄 What's Included

All features from v1.0.4 plus the update fix:

• ✅ TCP Port Scanner (real network scanning)
• ✅ Internet Speed Test (Ookla CLI)
• ✅ Network Information (IP, DNS, Gateway)
• ✅ Ping & Traceroute Diagnostics
• ✅ Export to CSV
• ✅ Auto-update mechanism (now working properly!)

---

📦 Technical Details

Package: ntchk-v1.0.5-Portable.zip (1.29 MB)

Contents:

• ntchk.exe - Policy-friendly launcher (recommended)
• ntchk.bat - Fallback launcher
• ntchk.ps1 - Main PowerShell application
• speedtest.exe - Ookla CLI for speed tests
• src/ - PowerShell modules
• ui/ - XAML interface files
• assets/ - Icons and images
• config.json - Configuration file
• README.txt - User documentation

Requirements:

• Windows 10/11 or Windows Server 2016+
• PowerShell 5.1+ (built into Windows)
• .NET Framework 4.5+ (built into Windows)
• Internet connection for speed tests and updates

---

File Verification

Verify your download integrity using SHA256 checksums:

File: ntchk-v1.0.5-Portable.zip
SHA256: BE81A6493696C90521452EECD1E78CB1FE5BC633B7837B5DF5876149A6B95969
Size: 1.29 MB

✅ Verification Status: This checksum has been verified against the actual file and matches the published checksum on GitHub.

Quick Guide: How to Verify in PowerShell

Step 1: Download both files from GitHub releases:

• ntchk-v1.0.5-Portable.zip
• ntchk-v1.0.5-Portable.zip.sha256

Step 2: Open PowerShell in the download folder:

• Hold Shift + Right-click in the folder
• Select "Open PowerShell window here"

Step 3: Run the verification command:

Method 1: Simple Verification

# Calculate the checksum
Get-FileHash .\ntchk-v1.0.5-Portable.zip -Algorithm SHA256

# Compare with the checksum above

The hash should match exactly. If it doesn't, do not run the file - re-download from the official source.

Alternative Verification

You can also verify using the included .sha256 file:

# Read expected checksum
$expected = (Get-Content .\ntchk-v1.0.5-Portable.zip.sha256).Trim()

# Calculate actual checksum
$actual = (Get-FileHash .\ntchk-v1.0.5-Portable.zip -Algorithm SHA256).Hash

# Compare
if ($expected -eq $actual) {
    Write-Host "✓ Checksum verified - file is authentic" -ForegroundColor Green
} else {
    Write-Host "✗ Checksum mismatch - do not use this file!" -ForegroundColor Red
}

Verify Against GitHub Release

Verify the downloaded file directly from GitHub:

# Download checksum from GitHub release
$githubHash = (Invoke-WebRequest -Uri "https://github.com/MadAreYou/Network_Check_app/releases/download/v1.0.5/ntchk-v1.0.5-Portable.zip.sha256" -UseBasicParsing).Content.Trim()

# Calculate local file checksum
$localHash = (Get-FileHash .\ntchk-v1.0.5-Portable.zip -Algorithm SHA256).Hash

# Compare
if ($githubHash -eq $localHash) {
    Write-Host "✓ File matches GitHub release - verified authentic" -ForegroundColor Green
} else {
    Write-Host "✗ File does not match GitHub release!" -ForegroundColor Red
}

---

🐛 Known Issues

None reported in v1.0.5

---

📞 Support

If you encounter any issues:

1. Check upgrade-debug.log and update.log in the app folder
2. Open an issue on GitHub with log files attached
3. Include Windows version and PowerShell version ($PSVersionTable)

---

🙏 Thank You

Thank you for using ntchk! This update ensures a smooth auto-update experience for all future releases.

Upgrade now to get the fix and enjoy seamless updates going forward! 🚀

ntchk v1.0.4

ntchk v1.0.4 - Port Scanner & UI Enhancements 🔍

Release Date: November 25, 2025
Download: ntchk-v1.0.4-Portable.zip

---

🎯 What's New

🔍 TCP Port Scanner - New Diagnostics Tool

A powerful, real-time port scanning capability has been added to the Diagnostics tab!

Key Features:

• ✅ Real TCP Connect Scanning - Live port connectivity testing (no simulation)
• ✅ Flexible Port Input - Single ports, ranges, lists, or mixed formats
• ✅ Service Detection - Automatically identifies 24+ common services
• ✅ Smart Defaults - Scans 18 common ports when input is empty
• ✅ No Admin Required - Uses TCP connect method (like nmap -sT)

Supported Input Formats:

80                    # Single port
80,443,3389          # Multiple ports
1-1024               # Port range
20-25,80,443,3306    # Mixed (ranges + individual)

Service Name Detection:
The scanner automatically identifies common services like HTTP (80), HTTPS (443), SSH (22), RDP (3389), MySQL (3306), PostgreSQL (5432), and many more!

Default Common Ports:
When you leave the port field empty, it scans: 20-25 (FTP), 53 (DNS), 80 (HTTP), 110 (POP3), 143 (IMAP), 443 (HTTPS), 445 (SMB), 587 (SMTP), 993 (IMAPS), 995 (POP3S), 1433 (MSSQL), 3306 (MySQL), 3389 (RDP), 5432 (PostgreSQL), 5900 (VNC), 8080 (HTTP-Alt), 8443 (HTTPS-Alt)

---

✨ UI/UX Improvements

📐 Fixed Diagnostics Tab Layout

• Proper Grid Structure - 7-row grid prevents button displacement during output
• Scrollable Output - Output area expands properly with border styling
• Placeholder Text - Input fields show helpful examples: "example.com or 192.168.0.1"

🎬 Animated Progress Indicators

• Three-Dot Animation - Visual feedback with cycling dots (. .. ...)
• Clean Progress Messages - Shows scanned ports without flooding output
• Real-time Updates - Know exactly what's being tested

---

📦 Installation

1. Download ntchk-v1.0.4-Portable.zip
2. Extract to any folder
3. Double-click ntchk.exe (recommended)

---

🔄 Upgrading from v1.0.3

Simply download and extract v1.0.4 - your settings and exports are preserved!

---

✨ All Features Included

This is a feature enhancement release - all features from v1.0.3 are preserved:

• ⚡ Speed Test - Ookla Speedtest integration
• 🌐 Network Info - IP, DNS, Gateway, WiFi/Ethernet detection
• 🔧 Diagnostics - Ping, DNS Lookup, Traceroute, DNS flush, IP release/renew
• 🔍 Port Scanner - NEW! TCP port scanning with service detection
• ⚙️ Settings - Dark mode, auto-export, desktop shortcuts
• 🔄 Auto-Update - GitHub-integrated update system
• 📊 Export - JSON export for all results
• 🎨 Themes - Light/Dark mode support

---

🛡️ Policy-Friendly Features

ntchk maintains its enterprise-ready design:

• ✅ Zero VBScript (commonly blocked by corporate policies)
• ✅ Neutral naming (avoids "suspicious" keywords)
• ✅ Compiled .exe launcher (trusted by security software)
• ✅ No admin rights required for port scanning
• ✅ Fully auditable (open source)

---

🔧 Technical Details

Port Scanner Implementation:

• Method: TCP Connect Scan (System.Net.Sockets.TcpClient)
• Timeout: 1000ms per port
• Max Ports: 5000 per scan (safety limit)
• Output: Open/Closed statistics with service names

UI Architecture:

• Grid Layout: 7-row structure with proper spacing
• Animations: DispatcherTimer-based (500ms cycle)
• Event Handling: Async job execution with spinner
• Placeholder: Grid overlay technique for input hints

---

🚀 What's Next?

Future enhancements being considered:

• Additional diagnostic tools
• Enhanced export formats
• Network mapping features

---

📝 Full Changelog

See CHANGELOG.md for detailed version history.

Full Changelog: v1.0.3...v1.0.4

---

💬 Feedback & Support

Found a bug? Have a feature request?
Open an issue on GitHub Issues

Contact:

• Email: juraj.madzunkov@example.com
• LinkedIn: Juraj Madzunkov

---

Thank you for using ntchk! 🙏

v1.0.3

ntchk v1.0.3 - Policy-Friendly Edition 🛡️

🎯 What's New

Auto-Update System

• Automatic update checks on startup (configurable in Settings)
• Manual update check via "Check for Updates" button
• One-click installation - downloads and installs updates automatically
• Preserves your settings and exports during updates
• Update notification popup shows version comparison

Hidden PowerShell Window

• ntchk.exe - Launch app without console window (recommended)
• ntchk.bat - Enhanced launcher using policy-friendly methods

UI Improvements

• Current version display in Settings tab
• "Check for Updates" button (bottom-left of Settings)
• "Check for updates on startup" checkbox

🔧 Bug Fixes

• Fixed Contact popup display issue

---

📦 Installation

1. Download ntchk-v1.0.3-Portable.zip
2. Extract to any folder
3. Double-click ntchk.exe (recommended)

---

🔄 Upgrading from v1.0.2

Download and extract v1.0.3 - future updates will be automatic!

---

🛡️ Enterprise Security Edition

This release represents a major architectural shift for enterprise policy compliance:

Problem Solved

Previous versions used VBScript launchers and names containing "suspicious" keywords that triggered security policies on company laptops.

Solution: Policy-Friendly Redesign

• ✅ Zero VBScript - All VBScript code eliminated
• ✅ Neutral Naming - Rebranded to "ntchk" (Network Toolkit)
• ✅ Compiled Launcher - Pure .NET executable (ntchk.exe)
• ✅ Clean Architecture - Policy-compliant file structure

File Changes

Old Name	New Name	Status
NetworkCheckApp.ps1	ntchk.ps1	Renamed
Run-NetworkCheck.vbs	—	REMOVED
Run-NetworkCheck.bat	—	REMOVED
—	ntchk.exe	NEW
—	ntchk.bat	NEW

Before vs After

Before (v1.0.2)

• ❌ VBScript launcher flagged by security policies
• ❌ "Run-NetworkCheck" name triggered keyword alerts
• ❌ Blocked on company laptops

After (v1.0.3)

• ✅ Pure .NET executable (trusted by security software)
• ✅ Neutral "ntchk" naming (no suspicious keywords)
• ✅ Works on company laptops without exceptions
• ✅ Same powerful features, enterprise-ready packaging

---

✨ All Features Included

This is a packaging and naming update - all features from v1.0.2 are preserved:

• ⚡ Speed Test - Ookla Speedtest integration
• 🌐 Network Info - IP, DNS, Gateway, WiFi/Ethernet detection
• 🔧 Diagnostics - Traceroute, DNS flush, IP release/renew
• ⚙️ Settings - Dark mode, auto-export, desktop shortcuts
• 🔄 Auto-Update - GitHub-integrated update system
• 📊 Export - JSON export for all results
• 🎨 Themes - Light/Dark mode support

---

🚀 Assets

Full Changelog: v1.0.2...v1.0.3

---

Special Thanks to users who reported security policy issues - this feedback inspired the policy-friendly redesign! 🙏

Network Check v1.0.2 - Auto-Update System

🎉 What's New

Auto-Update System

• Automatic update checks on startup (configurable in Settings)
• Manual update check via "Check for Updates" button
• One-click installation - downloads and installs updates automatically
• Preserves your settings and exports during updates
• Update notification popup shows version comparison

Hidden PowerShell Window

• Run-NetworkCheck.vbs - Launch app without console window (recommended)
• Run-NetworkCheck.bat - Enhanced launcher using VBScript

UI Improvements

• Current version display in Settings tab
• "Check for Updates" button (bottom-left of Settings)
• "Check for updates on startup" checkbox

🔧 Bug Fixes

• Fixed Contact popup display issue

📥 Installation

1. Download NetworkCheck-v1.0.2-Portable.zip
2. Extract to any folder
3. Double-click Run-NetworkCheck.vbs

🔄 Upgrading from v1.0.1

Download and extract v1.0.2 - future updates will be automatic!

---

Full Changelog: v1.0.1...v1.0.2

Network Check v1.0.1 - Portability Fixes

🔧 Bug Fixes

• Portability Fix - Fixed hardcoded paths causing "Access Denied" errors
• App now works correctly when extracted to any folder location

✨ Improvements

• Added Run-NetworkCheck.bat - Easy double-click launcher
• Hidden window mode for cleaner execution

⚙️ Configuration

• config.json now auto-created with correct paths

📦 Installation

Download, extract, and run Run-NetworkCheck.bat - No installation needed!

Network Check v1.0.0

Features

• ✨ Speed Test - Powered by Ookla Speedtest CLI

  • Download/Upload speeds with real-time progress
  • Ping, jitter, and latency measurements
  • ISP and server information
  • Export results to JSON format

• 🌐 Network Information

  • Network name detection (WiFi and Ethernet)
  • Public and local IP addresses
  • Gateway and DNS server information
  • Auto-refresh with timestamp

• 🔧 Diagnostics Tools

  • Traceroute, DNS cache flush, IP release/renew
  • Winsock reset, ARP cache clear
  • Real-time output display

• ⚙️ Settings & Customization

  • Light/Dark mode themes
  • Export folder configuration
  • Desktop shortcut management

• 📞 Contact & Support

  • Email and LinkedIn links
  • Donation QR code (Revolut)

Installation

1. Download the ZIP file below
2. Extract to any folder
3. Run Run-NetworkCheck.bat

Requirements

• Windows 10/11
• PowerShell 5.1+ (pre-installed)
• Internet connection for speed tests