Why this happens
That prompt is one of the features Windows implements for devices connected as MTP devices. The most sure way to disable it is to connect your Galaxy SII in USB Mass Storage mode. This way, Windows will detect it as a normal flash drive and will transfer files like any other flash drive without caring about the type. Some (desired) more advanced functionality may be lost, however.
The two basic ways to stop this from happening:
Option 1: Changing the phone connection mode
Enabling Mass Storage mode on Galaxy SII ICS (Android 4.x) (source):
- Bring up Settings.
- Click More… (under Wireless and network).
- Then select USB utilities ~ Set USB cable connection mode.
- Select Connect storage to PC then.
- Connect USB cable from phone to PC.
- Select Turn on USB storage.
Option 2: Unregistering the
.dll for the Windows shell extension that handles this
If you wish to keep using MTP mode for whatever reason, there has been a thread created on microsoft Answers specifically addressing disabling this prompt. Specifically:
Well, I previously couldn't find references to that dialog in any
Windows 7 DLL file, so I thought that it wasn't Windows-related. But I
have now looked again and found references to it in wpdshext.dll. So
it does appear to be a standard Windows feature, my apologies.
I suggest that you try unregistering the DLL in question. Please open
the Start Menu, go to All Programs - Accessories, right-click Command
Prompt, and select Run as administrator. Then type the following
regsvr32 /u wpdshext.dll
You should probably restart after running the command.
I have not tried this method personally, and unregistering standard Windows DLLs may have unexpected consequences. If anything does go wrong, I recommend you start in Safe Mode and run
regsvr32 wpdshext.dll in an elevated command prompt.
Disabling the shell extension
This method may be safer than unregistering a
Find the extension named
Portable Devices Menu
Right click >
Disable Selected Items
Restart your computer (to be safe)