MakeOTF error when in Features tab

I’m having problems with glyphsapp when I try to update my features, I get this

MakeOTF error
— Source font: font.pfa
bad CharString format

But I still haven’t tried exporting my work, so I clicked on Details and they sent me to a Temp folder where some files have been saved (I’m assuming for backup).
Could it be a glyph that has a wrong name?
Thank you !

Yeah, try removing those stuff in the Temp folder and try updating the features again.

The error message is most likely caused by a illegal glyph name. This tutorial explains what you can do with the stuff in the temp folder:

Thank you for your answer,

This is what I got:

makeotfGlyphs [FATAL] — Source font:
makeotfGlyphs [FATAL] bad CharString format

Could it be related to this lam_alef-ar problem? Lam alef ligature

Should I delete the temp file as @Tosche said?

as I said, this is most likely caused by a illegal glyph name. Can you send me the file that I can have a look?

Ofcourse, Thank you!
is there a way to send the file in private?

send it to support [at] the domain of the website.