What does HRESULT 0x80040219 (TPC_E_INVALID_INPUT_RECT) mean?

TPC_E_INVALID_INPUT_RECT

Meaning

Windows documents TPC_E_INVALID_INPUT_RECT as “TabletPC inking error code. An invalid input rectangle was specified”. In practical terms, it is returned when an ink or recognition operation receives an input rectangle whose geometry is invalid for the requested context.

Where the failure belongs

This result belongs to Tablet PC ink, stylus and recognition. Tablet PC APIs span device enumeration, RealTimeStylus packet queues, ink-object lifetime and recognizer-specific capabilities. The numerical facility does not identify which Tablet PC layer produced the result. The relevant condition is that an ink or recognition operation receives an input rectangle whose geometry is invalid for the requested context.

Evidence to collect

• Capture 1: all four rectangle coordinates before marshaling.
• Capture 2: source coordinate space, DPI and transform matrix.
• Capture 3: target window bounds and recognizer guide configuration.

Likely causes

• Possible cause 1: left and right or top and bottom coordinates are reversed.
• Possible cause 2: the rectangle is empty when a non-empty guide is required.
• Possible cause 3: coordinate conversion mixes screen, client or ink-space units.

Diagnostic sequence

1. Confirm that the observed path matches this condition: an ink or recognition operation receives an input rectangle whose geometry is invalid for the requested context.

Practical scenario

A per-monitor-DPI conversion produces a negative-width recognition guide after a window moves between displays; normalizing the transformed rectangle removes it.

Correct handling and retry

• Corrective action 1: normalize and validate rectangle geometry after every coordinate conversion.
• Corrective action 2: use the documented coordinate space for the API.
• Corrective action 3: recompute bounds after DPI or display changes.

Retry guidance. Retry immediately only after supplying a corrected rectangle; unchanged geometry will fail deterministically. When retrying, avoid replay stale strokes, reorder stylus packets or reuse an invalid recognizer context.

Difference from nearby HRESULTs

E_INVALIDARG is a general argument failure; it identifies rectangle geometry in the Tablet PC contract.

Developer and operational guidance

Official Microsoft references

• Microsoft: generic COM error codes
• Microsoft: RecognizerContext
• Microsoft: StylusInput architecture