File not found: '. DCU' Solution

In the past few days, I have studied Delphi and startedProgramAlways Prompt: [fatal error] *. PAS (7): file not found: '*. DCU', cannot be understood. I learned from Google that I forgot to set the control path when installing the control.
 
Solution: open tools> environment options in the Delphi toolbar:
Add the control path to the library path on the library tab, that is, the path containing this file (*. DCU.
This article from Hu Kai blog http://www.7788sky.cn/, the original address: http://www.7788sky.cn/post/file-not-found-.dcu.html