Remote Outlook Problem

[EST7745]

Currently, we have our remote users accessing outlook by doing the following....

They have outlook installed on their computer...

We have the HOSTS file in Winnt\systems32\drivers\etc storing the IP address and hostname of the server

This setup has always seemed to work fine, however a few computers have stopped connecting to the exchange server all of the sudden.....no setting in the hosts file have been changed. In fact, no settings to anyone's knowledge have been changed period. Outlook will just timeout and say that the exchange server is available.......but we CAN ping it so how could it be unavailable??? Should I juggle the binding order around for outlook? Anything else I could try? Thanks!!

 

[Steve Bowman]

I discovered the same issue with several remotes, the issue is
Outlook uses port tcp 135 during the logon process (RCP)

MSBlaster also attacks on port tcp 135

most ISP currently are blocking tcp 135 to curb the spread of MSBlaster

Check with your ISP they are probably (if they admit to it) port 135. You will not be able to change their mind on this one. I am trying to find a work around.

Steve Bowman
steve.bowman@ultraex.com

 

[EST7745]

They are claiming that no filtering or port blocking is going on. Should I trust what they tell me? Are there any other things that I can check?

 

[larsin]

Don't trust what they tell you. It is them! We talked to over 9 people at SWB before we finally got an honest answer. Trouble is now, they refuse to put it back. Trying also to find a workaround using Pop3 for external clients.

 

[Steve Bowman]

Like I said

"Check with your ISP they are probably (if they admit to it) blocking port 135."

most ISP's will give incorrect info on this issue, also depending on the level of tech you get he/she might not even be aware of it. You need a core NOC tech to verify port block.

Steve Bowman
steve.bowman@ultraex.com