When naming files and folder, to avoid problems with your projects you should not use the following:
Punctuation such as comma, semicolon, apostrophe, quotes etc.;
Diacriticals such as acute, circumflex, umlaut etc.
Spaces and capitals can also cause problems, capitals for example are not differentiated from lowercase by some web servers. Spaces need to be encoded for use in web addresses, so you will see, for example ‘this%20is%20a%20space’ instead of ‘this is a space’. Whilst not a problem, it hinders readability and complicates passing URLs to others. Underscore or dash characters can be used in file names instead of spaces, they make it easier to read and are commonly used.
Instead of naming files and folders with those characters just keep to simple text, then in the Title field enter the text you want to be seen. There are also 'illegal' characters, those must not be used, you can read about illegal characters here.
See the image below, showing the edit view, for one way of changing a folder name and title, and another in explore mode, shown to the right.