Outlook keeps going offline

[enigmafyv]

We are starting to experience a problem, in mass, where Outlook 2003
clients are going offline numerous times a day. People know that they
can uncheck the 'Work Offline' option in the file menu or the status
bar. However, the client tends to go offline again sometimes within
minutes and other times within hours. I know this is an old topic and
I've seen some workarounds that seem to fix the problem temporarily
but even they break after a while.

One person posted unchecking 'Cached Mode' and after doing that it
seemed to have fixed the problem for a few weeks, but then the problem
came back. I've even checked the event viewer on the Exchange server,
but that's not giving any feedback related to this problem.

A byproduct of this problem is when someone unchecks 'Work Offline'
they are then prompted to log into the domain with their profile, and
this doesn't always work. The prompt that comes up is asking for the
user to authenticate against a different DC than normal. So when they
put in their credentials it doesn't accept it and it keeps asking
them. I've told some people to put in their username as
"username@domainname" and this tends to get them further. A second
username prompt will come up asking to authenticate against a second
DC and after that they are able to get into their client.

I'm not sure if this is virus related or DNS related or DC related or
what. I can't seem to find any answers and arent' really sure where
to look.

Does anyone have any ideas?

 

[neo [mvp outlook]]

Have you verified that your domain controllers (the ones that hold the
global catalog role) and DNS/WINS name resolution is in good health?

Other than that, the only time I have seen Outlook 2003/2007 jump to work
offline is because the connect to Microsoft Exchange is dropping. This
could be something simple like the NIC being put to sleep by the OS, to
something deeper within the network.