The requested resource is in use when Deleting printer Port

[Shadowwraith]

Ok. Something is weird there. You can try removing the printer via registry.

Go to the Start Menu
Type Regedit in the search box
Click on Regedit.exe to open Registry Editor

Backup your registry first!

Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print\Printers
Delete the folder(s) of the printer you want to remove
Close Regedit

Go to the Start Menu
Type Services in the search box
Click on Services to open the Services console (the one with the blue gears icon)

Right-click on Print Spooler
Click Restart
Close Services

Ok. Something is weird there. You can try removing the printer via registry.

Go to the Start Menu
Type Regedit in the search box
Click on Regedit.exe to open Registry Editor

Backup your registry first!

Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print\Printers
Delete the folder(s) of the printer you want to remove
Close Regedit

Go to the Start Menu
Type Services in the search box
Click on Services to open the Services console (the one with the blue gears icon)

Right-click on Print Spooler
Click Restart
Close Services

I had this same error and I think you pointed me in the right direction by resorting to the Registry to solve my problems.

I am running Windows 11 and these are the registry keys I needed to address:

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Printers\<DELETE the name of any printer that could have been using the port>

e.g. Home Printer
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Printers\Home Printer

When I searched for the Name of the port this is what action I performed:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Print\Monitors\Standard TCP/IP Port\Ports\< DELETE the name of the port I want to remove>

The name of the Printer port I wanted to delete, I named it, but others might have left the default:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Print\Monitors\Standard TCP/IP Port\Ports\Home_Printer

I continued to search the entire registry, but there were no more occurrences of My
Now I did this in Safe Mode, which being an old timer meant I needed to restart holding the shift key when I selected the Power Icon, select Troubleshoot, Advanced options, Startup Settings (Read the options to prepare yourself for what you'll want to look for), Restart

I chose option 5. Enable Safe Mode with Networking

I don't know if that was necessary, but I've had problems in the past where Windows hid items that were uninstalled, when in-fact there are lingering elements.

Afterwards, I rebooted and opened the Print Server Properties

You can go there via Settings > Bluetooth & devices > Printers & scanners > Scroll down to Related settings > Print Server Properties
You can do it directly thusly:
Open Command prompt as admin then type in this command

rundll32 printui.dll,PrintUIEntry /s /t1

Click on the Ports tab and see if the port has been deleted

Oddly enough, as I wrote this I also discovered printmanagement.msc which offers a slightly different interface but might also be useful

Usually, I find there is more than one way to skin a cat (Speaking metaphorically, ofc) so I just wanted to add that a lot of this is heuristic, so your mileage may vary. But what was key for me was looking in the registry after all other avenues had been explored, such as, making sure I had removed the printer that used the port the Microsoft way (the dead stupid way, not in the registry), checking all the other printers to make certain, none of them was using the port in question. Then doing my work on the registry in safe mode (not because it's safe, but because it is less tied down by -waves hands in the air- who knows what.)
Thanks, and good luck!