What Is Canon IJ Network Scanner Selector? Is It Safe to Disable at Startup?

What Is Canon IJ Network Scanner Selector?

Canon IJ Network Scanner Selector is a Canon utility that helps Canon scanning software find and use a compatible Canon printer or scanner over your local network. It is typically installed with Canon printer/scanner drivers or Canon scanning software.

On Windows, the process is usually cnmnsst.exe. Its job is not to print documents by itself. Instead, it helps the Canon software detect which network scanner to use, especially if you scan from Canon's own app rather than from the device's buttons or Windows' built-in tools.

If you use a Canon all-in-one printer over Wi-Fi or Ethernet and scan regularly, this utility may be part of that setup.

Is It Safe?

Usually, yes. cnmnsst.exe from Canon Inc. is normally a legitimate Canon background process.

Because malware can use familiar names, check that the file is in a Canon program folder and that the file's digital signature shows Canon Inc. In Task Manager, right-click the process and open its file location. If it is running from an unusual folder such as C:\Users\<name>\AppData, C:\Windows\Temp, or another random location, treat that as suspicious and investigate it.

If the file is in Canon's install folder under Program Files and signed by Canon, it is generally safe.

Should I Disable It at Startup?

For most people, yes, you can disable it at startup if you do not scan often. This utility is helpful, but it is not a core Windows component and it usually does not need to be running all day.

Disabling it may mean Canon's scanning software takes longer to detect the device, or you may need to open the Canon app manually before scanning. If you scan from the printer's front panel to your PC, or use Canon network scan features regularly, you may prefer to leave it enabled.

So the practical rule is simple:

• Keep it enabled if you frequently scan over the network and Canon's software depends on it.
• Disable it if you rarely scan, or only print.

Why Is It Using High CPU or Memory?

This process normally uses very little CPU and memory. If usage is high, common causes include:

• the Canon software repeatedly searching for a scanner that is offline
• a printer/scanner connection problem on Wi-Fi or Ethernet
• a stuck Canon background task after sleep, resume, or a network change
• a damaged Canon driver or utility install

Try closing Canon apps, restarting the PC, and power-cycling the printer/scanner. If the problem returns, update or reinstall the Canon driver/software package for your model from Canon's support site.

If cnmnsst.exe shows heavy usage and the file location or signature looks wrong, investigate it as potentially unwanted or malicious.

How to Disable or Remove It

If it appears in Startup, you can disable it without uninstalling Canon software. In Windows, open Task Manager > Startup apps or use a startup tool such as Kudu to disable the entry.

If you want to remove it completely, uninstall the related Canon scanner or printer software from Installed apps in Windows Settings. Only do that if you no longer use the Canon device, since removing the package can break scanning features.

If you still need printing but not Canon's extra utilities, you may be able to keep the basic driver and remove optional Canon software, depending on your model.

Where Kudu Helps

Kudu can show whether Canon IJ Network Scanner Selector is set to start with Windows and lets you disable or remove the startup entry without guessing where it is stored. If the process is active, Kudu's Performance Monitor can confirm whether cnmnsst.exe is actually using CPU or memory, and link it back to its startup item.

If the file location looks suspicious, Kudu's Malware Scanner can help check for persistence and suspicious behavior, but it should complement your antivirus rather than replace it.

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