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Everything posted by rvk

  1. rvk

    DelphiTwain on 64-bit

    So the call gives a TWRC_XFERDONE (successful) but the handle could still be invalid. The handle (hNative) is a TW_UINT32 (which is a Cardinal/32bit). I wonder if it shouldn't be a TW_Handle (which should be a NativeUInt and UInt64 on 64 bit). At least GlobalLock expects a THandle (which is UInt64 on 64 bit). Doesn't seem really wise to stuff a handle in an Cardinal/32bit on 64 bit (which like David already mentioned, could be just a simple 32/64 bit truncation error). Strange this worked locally on the machine itself but fails on RDP. Maybe the handle-numbers are much larger and it fails.
  2. rvk

    DelphiTwain on 64-bit

    Are your connecting client, the used mstsc.exe and RDP-session (including your app) ALL 64 bit? (If not, you can't rely on the Virtual Channel Client DLL) Did you check the numerical value of hNative (i.e. not being 0)?
  3. rvk

    DelphiTwain on 64-bit

    So, the drivers are not loaded on the server itself? I'm not familiar with Virtual Channels in RDP, but I think this would mean you have the DLL on the local client and want the application, which runs on the server side in RDP, have access to the local scanner through the Virtual Channels-technology? Just like a Redirected Printer uses Virtual Channels. That's a whole lot of places where things can go wrong (that's why I asked if the scanner and drivers and DLL where locally on the server side in the RDP session itself). What was the value of the return-code on this line (in TTwainSource.TransferImages for TransferMode ttmNative): rc := Owner.TwainProc(AppInfo, @Structure, DG_IMAGE, DAT_IMAGENATIVEXFER, MSG_GET, @hNative); That seems to be where hNative gets its value (which fails). It seems the value is not checked for success there ( if rc <> TWRC_SUCCESS then ... should give error )
  4. rvk

    SSL certificate for VCL Application Exe

    YIKES. $474/year for a Code signing certificate ????? Shouldn't be any more than $100/Year or so via some Sectigo reseller. Examples here and here. You'll need a Code signing certificate ("SSL" EV won't do and I've never needed an EV Code certificate). I also never seen the icon disappear. What tool do you use to sign and what command line options?
  5. rvk

    DelphiTwain on 64-bit

    Are you using a redirected scanner in WTS? Or is the scanner-software (and 64bit driver) directly installed on the WTS machine? Does the DelphiTwainDemo2 example work in WTS? Not sure what you mean by this? In Windows Terminal Services (now called Remote Desktop Services, RDS) you also just run plain applications, don't you? Or do you mean it's running under Windows Services? (which is hugely different)
  6. rvk

    DelphiTwain on 64-bit

    Hard to say what could be the cause without example-source of DLL and calling procedure.
  7. rvk

    DelphiTwain on 64-bit

    On 64 bit it worked for me but I did't have any scan-sources. WIA sources are 32-bit and not visible in 64 bit for me. Installing the VueScan gave me a 64 bit source. What Delphi version do you use? Are you using VLC of FMX? Did you try the DelphiTwain\examples\VCL2\DelphiTwainDemo2 example? (which worked for me on 64 bit)
  8. rvk

    DelphiTwain on 64-bit

    So you provided a "bad value" Here it works fine with VueScan as 64 bit scan-sourcedriver. What/which scannerdriver did you try/use?
  9. rvk

    Suggestions for a message layout

    But that's how we recognize the administrators 😁 (although that information is also under the avatar-hoover.) I find that information useful to see in one glance. Hovering over the avatar hides it too much for me. +1 for the other suggestions although I wonder how much the layout can be changed from the default via themes (because this is based on standard forumsoftware). Ah well, there is always greasemonkey