Reply to an email with address who has capital letters

Hello i love this soft but i have a bug

mail no longer leaves when asked to reply to an email with the email address of the recipient who has capital letters


I can’t replicate this using Mailspring 1.9.1 on Linux - sending an email to an all-caps address works fine for me. Can you provide more details, like a (redacted) email format that fails, mail host etc.?

this error occurs by replying an email from this address

From: Lauriane JASCHKE <>

Same thing happened to me recently. I had an error when I tried to send a mail to an address written in capital letters (
Modified the address in the contact book to be lower case only and it seems to work.

but where is the contact book in mailspring ?

Here (on Linux, Mailspring 1.9.1), I can open it from the menus as Windows > Contacts.

merci, but the problem is not in contact window but :
when I request to reply to a message sent from an email address with uppercase letters the correspondent does not receive my reply.
I would very much like the concern to be resolved so I can reuse mailspring

Sorry for the confusion @deapobf - in your last post you seemed to be asking where the contact book was, and that’s what I tried to help with. I understand that the original post is about something else entirely!