@medvidec It’s impossible to know for sure without seeing your code, but I doubt the issue has anything to do with Notepad++. If this “global variable” is supposed to be shared between multiple C++ source files, you have to do the following: declare the variable in a header file as extern, e.g.: // your_header.h #include <string> extern const std::string configFile; include “your_header.h” in every source file that uses configFile . provide a definition (at global scope) of configFile in one (and only one) of the source files that includes “your_header.h”: // source_file.cpp #include "your_header.h" // ... const std::string configFile = "/plugins/config/verilogConfig.txt"; // ... You can read about storage class specifiers to learn more.