System validation error + not exporting lowercase only in TTF


I’m pretty new to this program and things have been going swimmingly until I decided to add some lowercase glyphs and an apostrophe or single quote.

Now, unlike before, when I export as a TTF the lowercase doesn’t show up and when I try exporting as an OTF I get a system validation error when I try to install.

Also, I think I must have accidentally toggled some state, but my capital A now has a bunch of lines underneath it? is this to set the leading or something? I could have sworn they weren’t there before.

I have tried unchecking the Autohint box when I export as I read in other posts that might be the issue but nothing has changed!

You most likely have a font cache problem. Did you read this: and

Can you post a screenshot of the lines underneath the A?

Thanks! I will try those!

Here’s what happening with the A

Thanks for your help!

Can you send me the .glyphs file (to support at this domain)?