win7清除占用的端口号

https://superuser.com/questions/408976/how-do-i-clean-up-com-ports-in-use

 

方法1.使用Device Remover  https://www.majorgeeks.com/files/details/device_remover_543c.html

Just load it up, click on "Display Mode", "Show only hidden/detached devices", Check "Ports" (which selects all the unused com ports), then click "Remove all checked", and confirm the removal when the warning appears.

 

 

 

方法2.

Run Device Manager from elevated command line:

> set DEVMGR_SHOW_NONPRESENT_DEVICES=1
> devmgmt.msc

Enable "Show hidden devices" in the menu, and uninstall grayed-out COM ports.

 

方法3：

 

I found a useful answer at How to clear or Reset COM port ?

1. Click start → Run → type regedit and click OK button
2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter
3. Now on the right panel, you can see the key ComDB. Right-click it and click modify
4. In value Data section select all and delete reset to zero (0)
   Its 32 bytes with 8 bits in each byte in hexadecimal representation. A bit of value 1 makes a port number (1...256) reserved. The first 8 ports are in two leftmost hexadecimal values, bits ascending from lowest to highest right to left, the next 8 ports are in the second two and so on: hex F3 24 would be binary 1111 0011 0010 0100, which means that following ports are used: 1, 2, 5, 6, 7, 8 (1111 0011) and 11, 14 (0010 0100).

 

1. Close the registry editor and then restart your computer. If you set the value to 0 all COM ports are free.

You may need to reinstall any USB-to-serial converter.