V20 L_IsTwainAvailable() Fails

Leadtools V20 I seem to be seeing a situation where L_IsTwainAvailable() fails if the last selected twain device is old. Even though there are multiple twain devices installed on the PC.
If the first one encountered is pre V1.9 the program including the twain sample project fails like there are non installed. Then if I select another through ScandAll 21 then the L_IsTwainAvailable() returns true.
Is this expected behavior? Has another else run into this?

Hello Andrew,

I emailed you a few minutes ago with this information, but it might be helpful to someone else who seems this thread. I have come across this issue myself, and the cause appears to be your default Twain device being offline. If you launch a program such as Twacker (or for 64-bit), and select an online scanner as the default, the SDK should properly recognize all the devices. I believe another alternative is to explicitly set the Twain version before using any functionality (such as the L_IsTwainAvailable method):

C: L_TwainSetVersion
C++: LTwain::SetVersion
.NET: TwainSession.SetVersion

For more information about setting the Twain version, refer to the following documentation page:
https://www.leadtools.com/help/leadtools/v20/dh/to/setting-which-twain-specification-version-to-use.html

Thanks,