Disabling fsquirt.exe should not shut down everything.  It is responsible for file transfer only.

The bluetooth profile you want to disable is called OBEX and there is indeed a way to disable specific profiles in Windows.. unfortunately.. the REAL way to do it seems to be mostly undocumented.

 This link points to data that shows that the mechanism exists and uses CSPs (configuration service providers) through windows client management.  I know NOTHING about CSPs.. I am not an admin.  If you DO, I would use the section in the middle of the link above to enable only the BT profiles that you want.  Search that page for OBEX and you will find your stuff!

I did quite a bit of research on this (just now) and it also looks like the implementation is still a moving target.

I DID find your fsquirt.exe solution that should have worked for you.

How do I unhook Fsquirt.exe? Software developers that desire to replace the in-box Bluetooth File Transfer Wizard with a proprietary application can unhook Fsquirt.exe from the underlying transfer wizard mechanism by performing the following steps: 
* Create a DWORD value that is named DisableFsquirt under the HKLM\System\CurrentControlSet\Services\Bthport\Parameters key in the registry. * Set the value of DisableFsquirt to 0x1 * Either reboot or run the following command in a command prompt window: fsquirt.exe -UnRegister

This information  came from MS here .

It should work. In the future, we will probably (hopefully) have a less stupid solution.


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or...

How about writing a logon script or DevCon that disables it?

DevCon (Devcon.exe), the Device Console, is a command-line tool that displays detailed information about devices on computers running Windows. You can use DevCon to enable, disable, install, configure, and remove devices. https://learn.microsoft.com/en-gb/windows-hardware/drivers/devtest/devcon

Modifying the registry item might also work.

HKEYLOCALMACHINE\SYSTEM\CurrentControlSet\services\BTHPORT\Parameters

Value name DisableFsquirt

Value type REG_DWORD

Value data 0x1 (1)

Hope this resolves your Query !!