The Trusted File Manager (TFM) is case sensitive for files and directories.  Therefore a filename or directory named `README` is not the same as `readme`  or `Readme`.  However, by default, windows and Mac OS are case insensitive which means attempting to read or load a file named README, will also find files or directories named readme or Readme.

Normally this will not cause any problems and by being case sensitive, you will be able to store files named `Readme`, `README`, and `readme` all in the same directory.  However, some applications make assumptions about the file system being case insensitive and will save a file named `README` but then try to load it using a case insensitive name such as `readme`.  In this case loading the file with the wrong name.  When working with programs that make assumptions about the case insensitive file names, make sure to save the file name in a format that will be used by the program.

The situation can also occur when attempting to run a program that is stored in a TFM Repository.  The file name "abc.dll" may exist but the program will try to load "ABC.dll" or "abc.DLL" or similar.  In these cases, the correct DLL file will not be found and the program will fail to run  The program will probably display an error message about a missing file.  Simply rename the file to the name expected by the program and it should resolve the problem.  In some cases, you may need to copy the missing file since different parts of the program may look for ABC.dll in one place and then ABC.DLL in another.