I read the question no error window in dev c++ to find the answer to the same problem I was facing. I followed the answer but I'm encountering a further problem as my floating report window has no log space or options. It's just a floating window and I do not know what to do with it. This is a silly extension to that question, but please help me- I'm stuck for long.
After you check the view>floating report window option , you have to right click on the floating window and click resize option and drag the floating window down .
And you will be able to see your lost error window again.