⚠️ 1 verified solutions available for Error 15203 — Last updated 2026-03-13
Error 15203 📋

Fix ERROR_MCA_MCCS_VERSION_MISMATCH — Windows Error Code 15203

Error 15203 (ERROR_MCA_MCCS_VERSION_MISMATCH) is a Windows Internet & WinHTTP error that occurs when the mccs version in a monitor's mccs_ver capability does not match the mccs version the monitor reports when the vcp version (0xdf) vcp code is used.. This guide provides step-by-step solutions to resolve this issue.

🏷️ Code: 15203 📛 ERROR_MCA_MCCS_VERSION_MISMATCH 📅 Updated: 2026-03-13 ⏱️ 1 Solutions

🎮 Common Scenario: Are you experiencing Error 15203 while launching or installing AutoCAD? The solutions below directly address the system interactions specific to this application.

⚡ Quick Fix

Reset Internet Settings: Open Command Prompt as Administrator

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📑 Table of Contents
What is Error 15203? Common Causes Step-by-Step Solutions Prevention Tips Related Errors

💡 What is Error 15203?

Windows System Error Code 15203, known as ERROR_MCA_MCCS_VERSION_MISMATCH, is a Internet & WinHTTP error that occurs during WinHTTP, WinInet, and internet protocols. The error indicates that: The MCCS version in a monitor's mccs_ver capability does not match the MCCS version the monitor reports when the VCP Version (0xDF) VCP code is used. When this error is encountered, the Windows operating system was unable to complete the requested operation within the internet services subsystem. The error code 15203 is returned by the GetLastError() function and provides developers with a specific identifier to diagnose the root cause of the failure. The symbolic name ERROR_MCA_MCCS_VERSION_MISMATCH maps directly to this numeric code and is commonly referenced in Microsoft documentation, developer forums, and system logs. Understanding this error and its context within WinHTTP, WinInet, and internet protocols is essential for effective troubleshooting.

⚠️ Common Causes

  • Proxy misconfigured
  • SSL/TLS handshake failure
  • Client certificate expired
  • WinHTTP response timeout
📚 Comprehensive Guide

Resolving Cryptographic Provider and Certificate Chain Errors (CRYPT_E_BAD_MSG)

An encyclopedia on resolving failing SSL/TLS handshake errors, root certificate trust issues, and Windows Cryptographic Services failures.

Read the full guide →

✅ Step-by-Step Solutions

1 Reset Internet Settings
  1. Open Command Prompt as Administrator
  2. Run: netsh winhttp reset proxy
  3. Open Internet Options → Advanced → Reset
  4. Restart your browser and applications

🎬 Video Tutorials

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💻 Diagnostic Command

Run this PowerShell command to find related events in your system log:

Get-EventLog -LogName System -Newest 20 | Where-Object {$_.Message -like "*15203*" -or $_.Message -like "*ERROR_MCA_MCCS_VERSION_MISMATCH*"} | Format-List

💡 Open PowerShell as Administrator, paste the command above, and press Enter.

🛡️ Prevention Tips

  • Use centralized proxy management
  • Keep root certificates updated
  • Disable legacy SSL 3.0 protocol
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Last updated: 2026-03-13
📖
Based on Official Microsoft Documentation
Solutions Tested on Windows 10 & 11
Error codes sourced from Microsoft Win32 SDK. Updated 2026-03-13.
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