Outlook changes mail server and username

[The Manai'a]

I set up my email account in Outlook using:

mail server = mail.server.net
user name = myusername

and it works perfectly. A short time later, Outlook is unable to connect to
my mail server. I open the account settings, and Outlook has changed:

mail server = 127.0.0.1
user name = myusername/mail.server.net

When I manually change the mail server and username back to the original
settings, Outlook again works perfectly. I have to fix the settings several
times a day.

Why is Outlook changing these settings and how do I disable Outlook from
doing this?

 

[The Manai''a]

Thank you Neo. I turned off Trend Micro's POP email scanning function and the
problem went away.

 

[MRW]

Yes, but what if you prefer to have your AV program do its job? Is there a
way to avoid this problem without disabling the POP scanning?

 

[Brian Tillman [MVP - Outlook]]

Yes, but what if you prefer to have your AV program do its job?

It will still do its job even without the mail scanning.

Is there a way to avoid this problem without disabling the POP scanning?

Maybe. Does your AV program insert a "this message has been checked"
announcement in the messages you receive? This could be the source of the
problem, if so. Disable that certification and it may work without
interfering.