When starting, I get: Could not load or assembly or one of its dependencies. What to do?

Modified on Mon, 29 Sep at 4:02 AM

This message means Windows couldn’t load a required library (DLL) for the app. It’s usually a missing/disabled runtime, an out‑of‑date Windows component, or a security product blocking the file.


Quick fix (most cases)

  1. Run Windows Update → install all pending updates → Restart.
    Keeps code‑signing, TLS, and system components current.

  2. Repair/enable .NET Framework 4.8

    • Windows 10/11: Apps → Optional features → More Windows features → ensure .NET Framework 4.8 Advanced Services is checked. If it’s already on, uncheck → OK → restart → re‑enable to repair.

  3. Install/Repair Microsoft Visual C++ Redistributables

    • Install both 2015–2022 x86 and x64 packages (repair if already installed).

  4. Re‑download & reinstall CNC Simulator Pro

    • Right‑click installer → Properties → if you see Unblock, tick it → OK.

    • Verify the file is digitally signed by Zyntaxis SRL before running.

    • Temporarily pause AV or allow/restore if it quarantined a file, then re‑enable.


If you still get the error

  1. Note the exact name of the missing assembly shown in the error (e.g., System.Data.SQLite.dll, Blocks.dll).

  2. Try on another PC (helps rule out a local policy/AV issue).

  3. Send us a report (see template below).


Common causes & how to spot them

  • Out‑of‑date Windows components
    Symptoms: fresh install on older or rarely‑updated Windows; SmartScreen or TLS trust errors elsewhere.
    Fix: Windows Update + restart.

  • .NET Framework not present/healthy
    Symptoms: error appears immediately at launch; Event Viewer may show .NET Runtime exceptions.
    Fix: Enable/repair .NET Framework 4.8 (see steps above).

  • Missing VC++ runtime
    Symptoms: mentions a native DLL or api‑ms‑win‑crt failure.
    Fix: Install/repair VC++ 2015–2022 x86 & x64.

  • Antivirus quarantined a dependency
    Symptoms: file disappears after install; AV history shows a block/quarantine.
    Fix: Restore/allow the file and folder; add an exception; re‑install.

  • File is marked as downloaded/blocked
    Symptoms: installer runs but app fails; file shows Unblock checkbox in Properties.
    Fix: Unblock and reinstall.

  • 32/64‑bit mismatch (rare)
    Symptoms: error references provider/driver DLLs (e.g., database or USB drivers).
    Fix: Use the matching x86/x64 driver or app build.


What to send support (fastest resolution)

Email support@cncsimulator.com with:

Subject: Assembly load error at start-up 
Exact error text (copy/paste or screenshot): <text or image> 
CNC Simulator Pro version: <e.g., 4.0.1.4> 
Windows version: <e.g., Windows 11 Pro 23H2> 
What I tried already: <Windows Update / .NET repair / VC++ repair / reinstall / AV restore> 
Did it work on another PC? <yes/no>

Tip: If the dialog names a specific DLL, include that name.


Safety reminder

Only install from our official download links and verify the digital signature = Zyntaxis SRL. Never send passwords or payment details in tickets.


Bottom line: This error is almost always fixed by updating Windows, repairing .NET 4.8, installing the VC++ runtimes, and reinstalling with the file unblocked. If it persists, send us the exact error text and we’ll pinpoint the missing piece.


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