In windows 7 32-bit and 64-bit systems, scanner information cannot be found

[happycoderNo1]

Hello, I have developed a winform program using NAPS2 SDK and try to invoke scanner using twain. It can work normally in windows10 and 11, but it can not work normally in Windows 7 64 and 32 bit environment. The specific performance is that it takes too long to obtain scanner list and no data is returned. The detailed code is as follows. Could you please give me some help?

ScanningContext scanningContext = new ScanningContext(new GdiImageContext());
var controller = new ScanController(scanningContext);

scanningContext.SetUpWin32Worker();

// Program blocking
List<ScanDevice> scanDevices = await scanController.GetDeviceList(Driver.Twain);

[cyanfish]

I should document this somewhere but I'm not going to officially support Windows 7 with the SDK. The problem is that the worker is built with net8 which doesn't support Win7.

[cyanfish]

If you want you can build your own worker as mentioned here:

naps2/NAPS2.Sdk.Samples/TwainSample.cs

Lines 10 to 17 in 798fcaa

	// Scanning with TWAIN on Windows must happen from a 32-bit process. You can do this by building your exe as
	// 32-bit, but the better solution is to install the NAPS2.Sdk.Worker.Win32 Nuget package, which includes a
	// pre-compiled 32-bit NAPS2.Worker.exe. Then you only need to call ScanningContext.SetUpWin32Worker and you
	// should be able to scan with TWAIN.
	//
	// If you want to use a worker process but don't want to use a pre-compiled exe (or want to set up your own
	// logging etc), you can also build your own worker exe with the same name (and call WorkerServer.Run in its
	// Main method).