Subject: bug#67589: Bug with rmail (Emacs 29.1) and movemail 3.16 when password starts with dash symbol

From: Eli Zaretskii <[email-masked]>
Date: Sat, 02 Dec 2023 21:50:26 +0200

> Date: Sat, 02 Dec 2023 18:50:53 +0000
> From: [email-masked]
> 
> My remote mailbox password starts with a dash. I cannot use rmail 
> regardless to whether I store the password in my imaps:// URL or I 
> insert the password when prompted, and escaping the dash does not help 
> in either case.

Did you try to customize email-movemail-flags to give it the string
"--" (i.e. two dashes)?