Get all mail from different domains cause error

[davidck]

I set up many email accounts in Plesk.
And I fetched my emails all at once usually in Mozilla Thunderbird.

The problem is that when every time I fetch all emails at once, an error occurs.

However, if I fetch one by one, it works.

This wasn't a big problem until a customer of mine had the same problem and started to complain. He is using Outlook.

Any idea how to fix this?

 

[davidck]

The error shows:
An error occured with the POP3 server.

However, as I've mentioned before, it works if I just go one by one.

I just mail.mydomain.com as pop server.

 

[davidck]

Anyone help please?

The client contacted their ISP and they checked my server saying that Outlook does not support the IMAP format on my server. What is that supposed to mean?

If my question is not clear, let me know.