Strange Email Problem

[darkfly]

Hi all,

i have a very strange problem in Plesk 7.5, i have 100 domain hosted in one server, and in one (and only 1) of this account i have a very strange behavior:

-he have 30 mail box from 6 month
-this week, somes of the mail box (4) is not working, mnot sending email and not receving email
-i go to control panel do change password of the 4 account, to teste this problem in my computer, and surprise is impossible to change the password of this 4 account, plesk say me "password not good, more of 5 caractere etc...), but the new password is good, i try diferent and i have the same messages
-I found a workaround of this problem: delete and create again the mail box.

But, today, the customer tell me and say me "today all ohter mail box is not sending message and receving...), the same problem in the over mail box, and the same behavior, i can´t change the password and i have to create the mailbox again.

I checkd qmail-queue during my teste, and when the mailbox have the password problem, the emails is not send to qmail-queue, the email have desapear....

In the over 99 domain, with many mailbox i don't have any problem...

Any sugestion about this behavior? any solution?

Thx.