I installed an iOS app (.ipa file) on my iPad using iTunes for PC (with Windows 10 21H2).
The iPad's UDID is listed in Apple Developer Console list of devices. So it is a Developer test ipa for a test device.
I've connected the iPad to the PC after iTunes was started and was able to install the ipa by dragging it to iTunes and dropping it on the left lower "On my Device" pane.
I started iTunes after the iPad was connected to the PC and was able to install the ipa by dragging it to iTunes and dropping it on the left lower "Devices" pane.
iTunes 12.11.3.17 (64-bit)
iOS 15.4.1
iPad Pro 3th generation
MeisWietze
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