When I initialize, I get this error message

"Foldername, path or filenames in your sequence contain a comma or other non ASCII characters.

This prevents the Exif-Data from being loaded.
Please rename the folder/files."

What problems will this create? Also what is an example of a proper filename/pathname?

Special chars, comma, etc. - if you tell me the pathname you tried, maybe then I can tell you what's wrong with it.