Reinstalling drivers for various devices can result in a large number of non-existent or unused COM ports. Removing such ports does not require special knowledge and does not imply the use of additional special programs.
Instructions
Step 1
To display all hidden ports, call the main system menu by clicking the "Start" button and go to the "All Programs" item. Expand the "Standard" link and open the context menu of the "Command Line" element by right-clicking. Specify the "Run as administrator" item.
Step 2
Type devmgr_show_nonpresent_devices = 1 in the Windows command interpreter text box and confirm the command by pressing the Enter function key. Enter the value cdWindowssystem32 into the command line and again confirm your choice by pressing the Enter key.
Step 3
Type the last command, start devmgmt.msc, into the command interpreter text box and start the Task Manager utility by pressing the Enter function key again.
Step 4
Expand the "View" menu of the upper service panel of the dispatcher and select the "Show hidden devices" item. Find all unused COM and virtual ports marked with a gray background.
Step 5
Sequentially call the context menu of each of them by clicking the right mouse button and select the "Delete" command.
Step 6
Another way to accomplish the same task is to go to the Control Panel item from the main Start menu. Expand the System link and click the Advanced button. Select the Environment Variables group and create a variable named devmgr_show_nonpresent_devices with a value of 1.
Step 7
Confirm the application of the changes made by clicking OK twice and close the "System" dialog box. Return to the "Control Panel" item and reopen the "System" link. Go to the Hardware section and expand the Device Manager node.
Step 8
Expand the "View" menu of the upper service panel of the dispatcher and select the "Show hidden devices" item. Find unused COM ports and delete them.
