what do you mean by invalid region??

also pls help with the following ques wid their ans in true or false manner.

  1. A window application must ensure that it calls PostQuitMessage() alteast once to terminate the message loop.

  2. 32 bit programs anre more immune to certain problem involving threads then 16-bit??

  3. The effect of HideCaret is additive.

  4. Repeat count is always 1 for key up message.

5' Window 98/NT are non preemptive multitasking enviroment.
6. Program can call WndProc indirectly.