The error message that I get is exactly the same as this issue:
https://bitbucket.org/jfh/machg/issue/304/p4d4-passwords-ending-in-cause-problems-on "mercurial reported error number 255 abort authorization failed"
My machine is a Macbook. On MacHg, I can clone but not pull and push. I can do push and pull when I use the terminal though.
However, my password doesn't end with an exclamation mark but it has capital letters and ^. I guess ^ is not accepted in a password string as well.
Where can I see the restriction of the password string?