@Hiroaki TANAKA, Thanks for posting in Q&A. From your description, it seems the Oracle client 19c is deployed via Intune win32 app does not show under "Setting > Apps > Installed apps.". If there's any misunderstanding, please let us know.
In General, when deploy app via Intune win32, Intune just warp it and deploy it to the device, then the app installation is referred to the app install command. To clarify our issue, please check the following information:
1.Please check if the app has been deployed successfully and if the app is already installed on the device side.
2, Manually run the install command on the affected device to install the app. As a note, if we configure install behavior as user, please run it under current user. But if we set it as system, please download PsExec tool to run as system account, then run the install command. Check if the app can be installed with this command and if it exists under "Setting > Apps > Installed apps"
3, How many devices are affected? Did it affect all the devices?
Please check the above information and if there's any update, feel free to let us know.
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