How should endpoint report error for TLP over PCI Express (PCIe)?
There is PCIe AER, which is a standardized format for error messages on PCIe, that has explicit error codes for unsupported transactions.
On Windows, this is reported through WHEA, on Linux, it shows up in the kernel log files in the absence of explicit driver support.
My expectation for Windows is that there, too, unhandled AER reports go into some sort of communal error log.