Error in opening the Library module file

Hi

I just create a copy of the same project. The compiling, linking
results of original one is ok.
However, the copied one is not.
The error message shows:
Error: Error in opening the Library module file. [MODA]
Error: Error in opening the Library module file. [MODT]

I use CVF6.6C. I've noticed the the external files are all included
including moda.f90 and modt.f90.
In MODA, I have a subroutine to USE MODT and in MODT, I have a
subroutine to USE MODA.
Two error messages are in some subroutines in MODA and MODT.
In main program I USE:
USE MODA
USE MODT

Sometimes I am suspecting that if the sequence of modules being USEd
matters (I mean first
MODT and the MODA), however, I test it and it doesn't make any
difference.

why is there compiling error if I copy the original project which is
compiled OK?
thank you in advance.

Mike

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