On Windows, if there is an error along the lines of "path/to/fbgem.dll" or one of its dependencies is missing when importing pytorch, you can check if it’s missing. Usually it is not missing, but its dependency libomp140libompthat’s missing. You can install this as part of the Microsoft Visual C++ redistributable. If that still does not work, you can directly download it from here and put it in C:\Windows\System32.