Summary
When launching Unreal Editor 5.7 on Windows with the virtual Wintab driver installed (e.g., via SuperDisplay) but the tablet not in use, the log shows:
LogStylusInput: Error: WintabAPI: Failed to query Specification Version (IFC_SPECVERSION, return value 4)
LogStylusInput: Error: WintabAPI: Failed to query Implementation Version (IFC_IMPLVERSION, return value 4)
This occurs even when the tablet input device is not active and the driver is disabled. The driver is installed but idle, yet the engine still probes it and logs the failure. In previous versions (< 5.7) this did not appear.
Impact:
Mostly cosmetic/log-noise. Doesn’t seem to break input functionality, but can confuse users and pollute logs. Potentially indicates overly aggressive initialization logic in the engine.
Platform / Versions:
Windows (example: Windows 10/11)
Unreal Engine 5.7
Virtual Wintab driver installed (SuperDisplay or similar)
Please select what you are reporting on:
Creative
What Type of Bug are you experiencing?
Stability
Steps to Reproduce
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Install a virtual tablet driver (such as SuperDisplay) or ensure a Wintab-capable device driver is present but not connected or active.
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Launch Unreal Editor 5.7 build on Windows.
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Observe Editor log tab or output window: the two “WintabAPI: Failed to query…” error lines appear at startup.
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Confirm stylus/tablet input is not actually used, and that the driver is idle—yet the log errors still fire.
Expected Result
No error logs appear when no tablet device is active. The engine should either skip Wintab version queries when no active context exists, or log a lower severity (like “Warning” or “Verbose”) instead of “Error”.
Observed Result
The errors are logged at startup any time a Wintab driver exists, regardless of activity state.
Impact:
Mostly cosmetic/log-noise. Doesn’t seem to break input functionality, but can confuse users and pollute logs. Potentially indicates overly aggressive initialization logic in the engine.
Platform(s)
Windows (example: Windows 10/11)
Unreal Engine 5.7
Virtual Wintab driver installed (SuperDisplay or similar)
Additional Notes
Please adjust stylus/input subsystem so that Wintab version queries are either skipped when no active tablet input is present or driver is disabled, or reduce severity to “Verbose” for return value 4 (context not available). This will avoid confusing error logs for setups where the driver is idle but installed.