Adding Custom library

sorry, doesnt english well.
help me, 5 hours search google

when i tried to including .h file in libraries\custom_directory, IDE says 'there're no such file or directory'.

i copy & paste .h file to already-exist library directory such as Servo and it works fine.

i use Library Manager. download Contributed library. and move .h file to this. it works fine.

why doesn't it work on my directory? does somebody know how to solve this problem?

The library MUST be in the libraries folder and MUST be in a folder with the same name as the header file.

What is the path to the library you've installed and what is the name of this library?

i've installed C:\Arduino\libraries\Test\ file name is Test.h and Test.cpp

thanks reply

Test.h in Test directory is undetected.

Test.h in Servo directory is detected.