Expand pdb file.

PDB is the program debug database, created when built on a debug mode. A program database (PDB) file holds debugging and project state information that allows incremental linking of a Debug configuration of your program.

The Visual Studio debugger uses the project.PDB file created by the linker directly and embeds the absolute path to the PDB in the EXE or DLL file. If the debugger cannot find the PDB file at that location or if the path is invalid (for example, if the project was moved to another computer), the debugger searches the path containing the EXE, the Symbol Path specified in the solution's Property Pages (Common Properties folder, Debug Symbol Files page). The debugger will not load a PDB that does not match the binary being debugged.