Try it :-)
I was playing with one package from Linux. I grab source code of package using Cygwin. This source code contained one funny file: aux.h.
Windows version of Vim refused to open this file with error message: Permission denied.
Even Notepad refused to open this file.
Finally Visual Studio gave me interesting hint about this aux.h file name:
I tried to zip this file by 7Zip and extract it back. Result was that 7Zip decompressed file as _aux.h.
Interesting issue. :-)