If you see a warning about an “unsigned driver,” use this method:
Press Windows Key + R again, type C:\Windows\System32\spool\PRINTERS and press .
If these quick checks don't work, proceed to the more thorough solutions below.
Select the corrupted port and click . If an error says the port is in use, restart your PC and try this step again immediately upon boot. could not install canon mf port monitor
If the Canon software wizard still refuses to install the custom MF Port Monitor, you can bypass it entirely by installing the printer using native Windows printing ports.
Locate the downloaded Canon driver setup file (usually Setup.exe ). Right-click the file and select . Click Yes on the User Account Control (UAC) prompt.
The error is a frequent issue that occurs when installing driver software for Canon imageCLASS or i-SENSYS multi-function printers. This error stops the installation process completely, leaving your printer unusable. It usually happens because of corrupted registry keys, software conflicts, missing Windows components, or active antivirus interference. If you see a warning about an “unsigned
Follow the prompts to see if the installation completes successfully. Step 2: Clear the Windows Print Spooler
Run the UNINSTAL.exe (note the single 'L') file as an administrator to wipe old registry entries and files.
Turn off the Windows Defender Firewall temporarily if you do not use third-party security software. Run the Canon installer again as an administrator. If an error says the port is in
Practical steps:
Alternatively, look for a program named CNMNPU.EXE on your installation media; this specifically deletes problematic Canon ports that may be causing the conflict. Open Settings > Apps > Advanced app settings .