If you're using Windows it will not let you create a file without a filename in Windows Explorer. It will give you the error "You must type a file name" if you try to rename a text file as .gitignore
To get around this I used the following steps
- Create the text file gitignore.txt
- Open it in a text editor and add your rules, then save and close
- Hold SHIFT, right click the folder you're in, then select Open command window here
- Then rename the file in the command line, with
ren gitignore.txt .gitignore