Is the font converter site broken?
I always get Please attach a font file before submitting the form
Hi!
If I only attach a font file in the form I also get the same error you are getting.
But if I also set font range or font characters then the converter works fine. Like in this picture:
Maybe the error message is indeed misleading.
For anyone else reading, if you just need standard characters, putting 0x20-0x7F (ASCII) in that range box like the screenshot shows seems to satisfy the converter.