D1251: D3D State Issue
The state of the Direct3D device changed when Direct2D was still using it. This may be indicative of a threading violation because only one thread may use the device at a time.
Possible Causes
The application may be using a single threaded D2D Factory on two different threads at the same time.
Possible Fixes
Make sure that the application is properly respecting Direct2D's threading policies.