NAPS versions after 6.1.2 don't show page after scanning (HP OfficeJet J4680)

[jantari]

Hello.

I am unfortunately experiencing a regression with NAPS versions 7.0+ (6.1.2 works).

I have an HP OfficeJet J4680 that I scan from using the TWAIN driver option.

The behavior in 6.1.2 (working) is:

1. I hit "Scan" in NAPS
2. The printer starts scanning (I can hear it)
3. The scanned page shows up in NAPS

in 7.0+ it is like this:

1. I hit "Scan" in NAPS
2. The printer starts scanning (I can hear it)
3. The scanned page DOES NOT appear in NAPS

I am currently still using a portable version of 6.1.2 to scan, but probably this affects more printer models than just mine so I think it's probably worth fixing or getting help on here. Thanks!

[cyanfish]

Can you try this test version and follow these instructions to collect debug logs? Except find the debuglog.txt file in the Data folder of the extracted test version instead of in your user folder.

naps2-7.1.2-testtwain.zip

[jantari]

Of course, here is the debuglog.txt that was generated:

debuglog.txt

2023-11-27 19:19:48.0305 8312 Debug: Using new dsm. 
2023-11-27 19:19:48.0858 8312 Using TWAIN DSM: C:\Users\jantari\Downloads\naps2-7.1.2-testtwain\App\lib\_win32\twaindsm.dll 
2023-11-27 19:19:48.0858 8312 NAPS2.TW - Opening session 
2023-11-27 19:19:48.1038 8312 Debug: Thread 1: OpenManager. 
2023-11-27 19:19:48.1318 8312 NAPS2.TW - StateChanged (to 3) 
2023-11-27 19:19:48.1318 8312 Debug: Using TWAIN2 memory functions. 
2023-11-27 19:19:48.1318 8312 NAPS2.TW - Finding source 
2023-11-27 19:19:48.1318 8312 Debug: Source id = 1 
2023-11-27 19:19:48.1318 8312 Debug: Source id = 2 
2023-11-27 19:19:48.1318 8312 NAPS2.TW - Opening source 
2023-11-27 19:19:48.1318 8312 Debug: Thread 1: OpenSource. 
2023-11-27 19:19:50.2553 8312 NAPS2.TW - StateChanged (to 4) 
2023-11-27 19:19:50.2553 8312 Debug: Registered callback2 OK. 
2023-11-27 19:19:50.2553 8312 NAPS2.TW - Configuring source 
2023-11-27 19:19:50.7137 8312 NAPS2.TW - Enabling source 
2023-11-27 19:19:50.7137 8312 Debug: Thread 1: EnableSource with NoUI. 
2023-11-27 19:20:16.9049 8312 NAPS2.TW - StateChanged (to 5) 
2023-11-27 19:20:16.9099 8312 Debug: Thread 1: CallbackHandler at state 5 with MSG=XferReady. 
2023-11-27 19:20:16.9099 8312 Debug: Got TWAIN msg XferReady 
2023-11-27 19:20:16.9099 8312 NAPS2.TW - StateChanged (to 6) 
2023-11-27 19:20:16.9099 8312 Debug: Trying to raise event TransferReadyEventArgs on thread 1 without sync. 
2023-11-27 19:20:16.9099 8312 NAPS2.TW - TransferReady 
2023-11-27 19:20:16.9449 20924 TWAIN PageStart w 1700 h 2338 
2023-11-27 19:20:18.5341 8312 NAPS2.TW - StateChanged (to 7) 
2023-11-27 19:20:18.5362 8312 Debug: Trying to raise event DataTransferredEventArgs on thread 1 without sync. 
2023-11-27 19:20:18.5362 8312 NAPS2.TW - DataTransferred 
2023-11-27 19:20:18.5362 8312 Error sending TWAIN data transfer event System.NullReferenceException: Object reference not set to an instance of an object.
   at ByteString Google.Protobuf.ByteString.CopyFrom(params byte[] bytes)
   at TwainMemoryBuffer NAPS2.Scan.Internal.Twain.TwainSessionScanRunner.ToMemoryBuffer(byte[] buffer, TWImageMemXfer memInfo)
   at void NAPS2.Scan.Internal.Twain.TwainSessionScanRunner.DataTransferred(object sender, DataTransferredEventArgs e)
2023-11-27 19:20:18.6926 8312 NAPS2.TW - StateChanged (to 6) 
2023-11-27 19:20:18.6926 8312 Debug: Thread 1: CallbackHandler at state 6 with MSG=CloseDSReq. 
2023-11-27 19:20:18.6926 8312 NAPS2.TW - StateChanged (to 5) 
2023-11-27 19:20:18.6926 8312 Debug: Got TWAIN msg CloseDSReq 
2023-11-27 19:20:18.6926 8312 Debug: Thread 1: DisableSource. 
2023-11-27 19:20:18.6926 8312 NAPS2.TW - StateChanged (to 4) 
2023-11-27 19:20:18.6926 8312 NAPS2.TW - SourceDisabled 
2023-11-27 19:20:18.6926 8312 NAPS2.TW - Finishing with completion 
2023-11-27 19:20:18.6926 8312 Debug: Thread 1: CloseSource. 
2023-11-27 19:20:18.7526 8312 NAPS2.TW - StateChanged (to 3) 
2023-11-27 19:20:18.7536 8312 Debug: Thread 1: CloseManager. 
2023-11-27 19:20:18.7536 8312 NAPS2.TW - StateChanged (to 2) 

[cyanfish]

Thanks, that's helpful, can you try this one now and see if it makes a difference:

naps2-7.1.2-testtwain2.zip

[jantari]

That version worked again! And it produced the following debuglog:

debuglog.txt

2023-11-28 17:38:21.1692 24508 Debug: Using new dsm. 
2023-11-28 17:38:21.2308 24508 Debug: NTwain internal message loop is starting. 
2023-11-28 17:38:31.1053 24508 Debug: Thread 14: OpenManager. 
2023-11-28 17:38:31.1893 24508 Debug: Using TWAIN2 memory functions. 
2023-11-28 17:38:31.1913 24508 Debug: Source id = 1 
2023-11-28 17:38:31.1913 24508 Debug: Source id = 2 
2023-11-28 17:38:31.1913 24508 Debug: Thread 14: CloseManager. 
2023-11-28 17:38:46.0615 16308 Debug: Using new dsm. 
2023-11-28 17:38:46.1280 16308 Debug: Thread 1: OpenManager. 
2023-11-28 17:38:46.1590 16308 Debug: Using TWAIN2 memory functions. 
2023-11-28 17:38:46.1610 16308 Debug: Source id = 1 
2023-11-28 17:38:46.1610 16308 Debug: Thread 1: OpenSource. 
2023-11-28 17:38:49.6595 16308 Debug: Registered callback2 OK. 
2023-11-28 17:38:50.1739 16308 Debug: Thread 1: EnableSource with NoUI. 
2023-11-28 17:39:16.4863 16308 Debug: Thread 1: CallbackHandler at state 5 with MSG=XferReady. 
2023-11-28 17:39:16.4908 16308 Debug: Got TWAIN msg XferReady 
2023-11-28 17:39:16.4908 16308 Debug: Trying to raise event TransferReadyEventArgs on thread 1 without sync. 
2023-11-28 17:39:18.2297 16308 Debug: Trying to raise event DataTransferredEventArgs on thread 1 without sync. 
2023-11-28 17:39:18.2297 16308 Expected memory transfer, but got native transfer? 
2023-11-28 17:39:18.2537 16308 Debug: Thread 1: CallbackHandler at state 6 with MSG=CloseDSReq. 
2023-11-28 17:39:18.2537 16308 Debug: Got TWAIN msg CloseDSReq 
2023-11-28 17:39:18.2537 16308 Debug: Thread 1: DisableSource. 
2023-11-28 17:39:18.2537 16308 Debug: Thread 1: CloseSource. 
2023-11-28 17:39:18.3212 16308 Debug: Thread 1: CloseManager. 

[mahaaxinf]

I have the same behavior after having updated to version 7.1.2.0 portable with my HP OfficeJet 4500

The debug log probably shows the reason:

2023-12-07 11:57:53.8984 19744 Debug: Using new dsm.
2023-12-07 11:57:53.9652 19744 Debug: Thread 1: OpenManager.
2023-12-07 11:57:53.9890 19744 Debug: Using TWAIN2 memory functions.
2023-12-07 11:57:53.9890 19744 Debug: Source id = 1
2023-12-07 11:57:53.9890 19744 Debug: Thread 1: OpenSource.
2023-12-07 11:57:55.3404 19744 Debug: Registered callback2 OK.
2023-12-07 11:57:55.4021 19744 Debug: Thread 1: EnableSource with NoUI.
2023-12-07 11:58:15.2190 19744 Debug: Thread 1: CallbackHandler at state 5 with MSG=XferReady.
2023-12-07 11:58:15.2190 19744 Debug: Got TWAIN msg XferReady
2023-12-07 11:58:15.2259 19744 Debug: Trying to raise event TransferReadyEventArgs on thread 1 without sync.
2023-12-07 11:58:16.5236 19744 Debug: Trying to raise event DataTransferredEventArgs on thread 1 without sync.
2023-12-07 11:58:16.5236 19744 Error sending TWAIN data transfer event System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
at ByteString Google.Protobuf.ByteString.CopyFrom(params byte[] bytes)
at TwainMemoryBuffer NAPS2.Scan.Internal.Twain.TwainSessionScanRunner.ToMemoryBuffer(byte[] buffer, TWImageMemXfer memInfo)
at void NAPS2.Scan.Internal.Twain.TwainSessionScanRunner.DataTransferred(object sender, DataTransferredEventArgs e)
2023-12-07 11:58:16.5516 19744 Debug: Thread 1: CallbackHandler at state 6 with MSG=CloseDSReq.
2023-12-07 11:58:16.5516 19744 Debug: Got TWAIN msg CloseDSReq
2023-12-07 11:58:16.5516 19744 Debug: Thread 1: DisableSource.
2023-12-07 11:58:16.5546 19744 Debug: Thread 1: CloseSource.
2023-12-07 11:58:16.6116 19744 Debug: Thread 1: CloseManager.

[jantari]

This second test version @cyanfish linked me worked for me, pls try it: #241 (reply in thread)

[jantari]

I have tried again with NAPS version 7.2.1 and it works now, just the same as it did with v6.1.2 - thanks a lot!