Commander fails to load after updating OR Antivirus/Windows blocks Commander from running
Commander Not Opening or Showing Virus Warnings?
We’ve had a small number of users reach out after updating Commander, reporting that the software won’t open or that their system is showing virus warnings.
If that’s happening to you, don’t worry. This is a known and common situation, and in almost all cases it can be resolved quickly.
Why This Happens
Commander itself is safe, tested, and working correctly.
Every update is tested across multiple Windows versions before release, and thousands of users successfully install updates without issue.
When problems like this occur, it is almost always due to:
Windows security settings
Third-party antivirus software incorrectly flagging files
In simple terms, your system is blocking or removing files that Commander needs to run.
Step 1: Reset Commander Version
If Commander is not opening, try resetting the version first:
Go to your C:\ drive
Open the folder: CNC3D Commander
Find and run “Version Resetter” (It has a similar icon to Commander itself)
Follow the prompts
This will reset Commander and force it to download the latest files again.
IMPORTANT NOTES:
The Version Resetter tool can be used any time you want to refresh and otherwise reset Commander files.
You will not lose any controller settings or user settings by using this tool!
If the Version Resetter file is missing, it has likely been removed by antivirus software. In that case, proceed to Step 2.
Step 2: Reinstall Commander (Recommended)
Download the latest installer here:
https://www.cnc3d.com.au/commander
Before running the installer:
Right click the downloaded file
Select Properties
Tick “Unblock” (if available)
Click OK
This helps Windows recognise the file as safe.
Then run the installer as normal.
Step 3: Check Your Antivirus Software
Windows defender Blocking Commander
If Windows Defender has blocked or removed parts of Commander, you can restore them by following these steps:
Open Windows Security
Click the Start menu
Search for “Windows Security” and open it
Go to Virus & Threat Protection
In the left-hand menu, click “Virus & threat protection” (as shown in Step 1 in the image)
Open Protection History
Click on “Protection history” to see recent actions taken by Windows Defender
Find the Blocked File
Look for entries marked as “Threat quarantined” or “Threat blocked”
Click on the item to expand it (Step 2 in the image)
Restore the File
Click the “Actions” dropdown (Step 3 in the image)
Select “Restore” (Step 4 in the image)
Allow the File (if prompted)
Confirm any prompts to allow or restore the file
This ensures it won’t be blocked again
IMPORT NOTES:
If files are not restored, Commander may not run correctly
This process is safe when restoring Commander files from the official installer
If the issue happens again, you may need to add Commander as an exception in Windows Security
Make sure to go through ALL of the recent quarantined threats for restore ALL of the files located in "C:\CNC3D Commander\" folder.
Once restored, try launching Commander again. In most cases, this resolves the issue immediately.
Updating Windows Defender manually
Please follow the steps below to clear cached detections and obtain the latest malware definitions.
1. Open command prompt as administrator and change directory to "C:\Program Files\Windows Defender "
2. Run “MpCmdRun.exe -removedefinitions -dynamicsignatures”
3. Run "MpCmdRun.exe -SignatureUpdate"
Alternatively, the latest definition is available for download here:
3rd party antivirus software blocking Commander
If you are using third-party antivirus software (such as Trend Micro, Norton, or similar), this is the most likely cause of the issue.
These programs can sometimes falsely flag safe software and block or delete important files.
To resolve this:
Temporarily disable your antivirus during installation, or
Add Commander as an exception in your antivirus settings
Once this is done, reinstall Commander and try again.
IMPORTANT NOTE:
If you are unsure how OR if the process above fails, you MUST reach out to your Antivirus vendor for help. They are ones falsely flagging our software and you are paying for their support!
Step 4: Turn off Smart App Control
Microsoft have an extra "security" feature now that limits software that is not on the Windows Store from being installed. This is increasing more and more as time goes on. Learn more
1. Click Start, type "Windows Security" and open it.
2. Click "App & browser control" on the left.
3. Click "Smart App Control settings".
4. Select "Off" and confirm.
5. Start Commander again. It will open normally.
IMPOTANT NOTE:
A heads-up before you do this: Windows only lets you switch Smart App Control off, not back
on again later (re-enabling it requires reinstalling Windows - that's Microsoft's design,
not ours). You are not left unprotected: Microsoft Defender, SmartScreen and all other
Windows security features remain fully active. Smart App Control is just an extra layer on
top, and most PCs don't have it enabled at all.
Still Having Issues?
If you’ve followed the steps above and are still having trouble and the issue is NOT a 3rd party antivirus program issue, please reach out to our support team. Priority support is complimentary during the standard CNC3D machine or controller warranty period. If your machine or controller is outside of the warranty period then priority support is available as a credit system. You can purchase priority support credits or view our contact details to start here: https://cnc3dbusiness.com/support
Why does this happen?
The bottom of this page covers these types of things in detail: https://www.cnc3d.com.au/commander-builds