Sometimes it is needed to access the project folder in Windows Explorer, but there is no easy way to do that using VS.
It can be solved by adding Explorer to External Tools in VS:
To set it up, click Tools, then External Tools..., then click Add. Now enter the following data:
Title: Windows Explorer
Leave Initial directory blank, and click OK. Now when you click Tools, Windows Explorer, Windows Explorer will open with the current file you are editing selected.