Mac Mail: anyone else have problems with passwords?

I switched from Entourage X to OS X Mail about a month ago, and since then,
I've been experiencing intermittent problems with one of my email accounts.
I have four accounts through Charter, and only rarely have a problem with
one of them. The error message is the general "mail cannot be received at
this time."

However, I also have email through my domain name, and a few weeks ago, it
just starting having all kind of problems not recognizing my username and
password. This has been a big pain the butt. My web hosting company's
performance has been really poor lately, so I thought it might be related
and that it was a good time to switch hosts, which I did. But I get the same
error with mac Mail on this one domain email account. Username and password
are not recognized.

If I open entourage, with the exact same settings, the mail downloads
instantly.

Is this a bug that anyone else is aware of, and is there a fix? I would
rather use Mail mail because I have so many email accounts and it's easier
to read them all in one screen rather than logging in/logging out, but I
just can't get this one email account to work.

Thanks,

Susan

I have a very similar problem with Apple's Mail. Seven e-mail accounts,
three with EarthLink and four Mac.com accounts and they are set to
download new mail every 10 minutes. The EarthLink accounts all work
perfectly but one of the Mac.com accounts goes offline somewhat
frequently and a warning pops up wanting me to re-enter my password.
And it's always the same account.

I've never been able to figure out what causes the problem. I've
deleted the Keychain entry for that one account several times to no
avail.

So what I do is pull down the Mailbox menu to Online Status, select the
recalcitrant account and take it back online. It always seems to do the
trick and then the account will work fine again for a day or two before
inexplicably going offline again.

If someone has a solution, I'd sure like to hear it.
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