Problem after reading binary file with windows gfortran

I face a very strange problem with my own (big) code when compiled with windows gfortran (no problem with old lahey compiler or linux gf):
when I read information in a binary file, everything is ok during the process but, afterwards, the code is unable to read correctly real data from the keyboard or from text files, the figures after coma being systematically ignored. If I type 0.3, it understands 0., if I type 3.1416, it understands 3. and so on. From the keyboard, I can “overcome” the problem by typing 31416E-4 (nice!), etc, but no medicine from text file.
Has anyone already experienced such curious behavior? Advices are welcome, thank-you.

Welcome to the forum!

Thje problem you sketch is something I have never encountered myself. It does not ring a single bell either. Can you experiment with taking out parts of the process of reading this binary file? Is there some point where the decimal point is recognised again? Could it be a setting in your program that changed the decimal separator from a point to a comma? An OPEN statement may contain the DECIMAL keyword to change the significance of a point and a comma,

Just a few random thoughts.