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I am writing a graphic miniport driver for Windows NT 4.0 - 5.1. I am stuck in the situation, that HwVidStartIo of my miniport driver never gets called.
I would expect that a display driver triggers the function calls by sending requests to videoprt.sys and then videoprt.sys calls my HwVidStartIo. But somehow no display driver cares about my miniport driver.
Do I need to announce or register my miniport driver to a display driver somehow?
When the system boots the flow is like this:
1. DriverEntry gets called
2. HwVidFindAdapter gets called
3. HwVidFindAdapter returns NO_ERROR/0x00
4. HwVidFindAdapter gets called
5. HwVidFindAdapter returns ERROR_INVALID_PARAMETER/0x57
6. HwVidFindAdapter gets called
7. HwVidFindAdapter returns ERROR_INVALID_PARAMETER/0x57
8. HwVidFindAdapter gets called
9. HwVidFindAdapter returns NO_ERROR/0x00
10. DriverEntry returns 0x00 (return value of VideoPortInitialize)
11. HwVidInitialize gets called
12. HwVidInitialize returns true/0x01
13. HwVidInitialize gets called
14. HwVidInitialize returns true/0x01
Also, when I start the display program from the control panel, I get the following message:
The currently selected graphics driver cannot be used. It was written for a previous version of Windows, and is no longer compatible with this version of Windows.
The system has been started using the default VGA driver.
This is really frustrating. I have no idea what Windows wants from me. Does someone know what I could do to figure out?
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