I have downloaded a zipped up library file (HMC5883L_Simple-master.zip), but when I try to add it to my sketch, the Arduino IDE (1.8.5) gives me the error message:
Specified folder/zip file does not contain a valid library
I have compared the zip file with others that I have downloaded and installed successfully, and the only real difference I can see is that it lacks a ‘library.properties’ file. But I can’t find any information on how to add such a file, assuming this is needed. There doesn’t seem to be any information in the Reference resources, for example.
Can anyone help me with this weird problem?